The discussion question/topic is on the following case Kansas v. Hendricks.This will be a good exercise going forward as you need to become familiar with reading cases and understanding the decisions. Your assignment is the following a minimum of 500 words:

1. Read the case
2. Critique the decision
3. Include your thoughts on SVP and if their term has max ’ed out is it legally and morally acceptable to prevent release and place them in n inpatient sexually treatment program

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346 OCTOBER TERM, 1996

Syllabus

KANSAS v. HENDRICKS

certiorari to the supreme court of kansas

No. 95–1649. Argued December 10, 1996—Decided June 23, 1997*

Kansas’ Sexually Violent Predator Act establishes procedures for the civil
commitment of persons who, due to a “mental abnormality” or a “per-
sonality disorder,” are likely to engage in “predatory acts of sexual vio-
lence.” Kansas filed a petition under the Act in state court to commit
respondent (and cross-petitioner) Hendricks, who had a long history of
sexually molesting children and was scheduled for release from prison.
The court reserved ruling on Hendricks’ challenge to the Act’s constitu-
tionality, but granted his request for a jury trial. After Hendricks tes-
tified that he agreed with the state physician’s diagnosis that he suffers
from pedophilia and is not cured and that he continues to harbor sexual
desires for children that he cannot control when he gets “stressed out,”
the jury determined that he was a sexually violent predator. Finding
that pedophilia qualifies as a mental abnormality under the Act, the
court ordered him committed. On appeal, the State Supreme Court
invalidated the Act on the ground that the precommitment condition
of a “mental abnormality” did not satisfy what it perceived to be the
“substantive” due process requirement that involuntary civil commit-
ment must be predicated on a “mental illness” finding. It did not ad-
dress Hendricks’ ex post facto and double jeopardy claims.

Held:
1. The Act’s definition of “mental abnormality” satisfies “substantive”

due process requirements. An individual’s constitutionally protected
liberty interest in avoiding physical restraint may be overridden even
in the civil context. Jacobson v. Massachusetts, 197 U. S. 11, 26. This
Court has consistently upheld involuntary commitment statutes that de-
tain people who are unable to control their behavior and thereby pose a
danger to the public health and safety, provided the confinement takes
place pursuant to proper procedures and evidentiary standards. Fou-
cha v. Louisiana, 504 U. S. 71, 80. The Act unambiguously requires a
precommitment finding of dangerousness either to one’s self or to others,
and links that finding to a determination that the person suffers from a
“mental abnormality” or “personality disorder.” Generally, this Court
has sustained a commitment statute if it couples proof of dangerousness

*Together with No. 95–9075, Hendricks v. Kansas, also on certiorari to
the same court.

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Syllabus

with proof of some additional factor, such as a “mental illness” or “men-
tal abnormality,” see, e. g., Heller v. Doe, 509 U. S. 312, 314–315, for
these additional requirements serve to limit confinement to those who
suffer from a volitional impairment rendering them dangerous beyond
their control. The Act sets forth comparable criteria with its precom-
mitment requirement of “mental abnormality” or “personality disorder.”
Contrary to Hendricks’ argument, this Court has never required States
to adopt any particular nomenclature in drafting civil commitment stat-
utes and leaves to the States the task of defining terms of a medical
nature that have legal significance. Cf. Jones v. United States, 463 U. S.
354, 365, n. 13. The legislature is therefore not required to use the
specific term “mental illness” and is free to adopt any similar term.
Pp. 356–360.

2. The Act does not violate the Constitution’s double jeopardy prohi-
bition or its ban on ex post facto lawmaking. Pp. 360–371.

(a) The Act does not establish criminal proceedings, and involun-
tary confinement under it is not punishment. The categorization of a
particular proceeding as civil or criminal is a question of statutory con-
struction. Allen v. Illinois, 478 U. S. 364, 368. Nothing on the face of
the Act suggests that the Kansas Legislature sought to create anything
other than a civil commitment scheme. That manifest intent will be
rejected only if Hendricks provides the clearest proof that the scheme
is so punitive in purpose or effect as to negate Kansas’ intention to deem
it civil. United States v. Ward, 448 U. S. 242, 248–249. He has failed
to satisfy this heavy burden. Commitment under the Act does not im-
plicate either of the two primary objectives of criminal punishment: ret-
ribution or deterrence. Its purpose is not retributive: It does not affix
culpability for prior criminal conduct, but uses such conduct solely for
evidentiary purposes; it does not make criminal conviction a prerequi-
site for commitment; and it lacks a scienter requirement, an important
element in distinguishing criminal and civil statutes. Nor can the Act
be said to act as a deterrent, since persons with a mental abnormality
or personality disorder are unlikely to be deterred by the threat of
confinement. The conditions surrounding confinement—essentially the
same as conditions for any civilly committed patient—do not suggest a
punitive purpose. Although the commitment scheme here involves an
affirmative restraint, such restraint of the dangerously mentally ill has
been historically regarded as a legitimate nonpunitive objective. Cf.
United States v. Salerno, 481 U. S. 739, 747. The confinement’s poten-
tially indefinite duration is linked, not to any punitive objective, but to
the purpose of holding a person until his mental abnormality no longer
causes him to be a threat to others. He is thus permitted immediate
release upon a showing that he is no longer dangerous, and the longest

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348 KANSAS v. HENDRICKS

Syllabus

he can be detained pursuant to a single judicial proceeding is one year.
The State’s use of procedural safeguards applicable in criminal trials
does not itself turn the proceedings into criminal prosecutions. Allen,
supra, at 372. Finally, the Act is not necessarily punitive if it fails to
offer treatment where treatment for a condition is not possible, or if
treatment, though possible, is merely an ancillary, rather than an over-
riding, state concern. The conclusion that the Act is nonpunitive re-
moves an essential prerequisite for both Hendricks’ double jeopardy and
ex post facto claims. Pp. 360–369.

(b) Hendricks’ confinement does not amount to a second prosecution
and punishment for the offense for which he was convicted. Because
the Act is civil in nature, its commitment proceedings do not constitute
a second prosecution. Cf. Jones, supra. As this commitment is not
tantamount to punishment, the detention does not violate the Double
Jeopardy Clause, even though it follows a prison term. Baxstrom v.
Herold, 383 U. S. 107. Hendricks’ argument that, even if the Act sur-
vives the “multiple punishments” test, it fails the “same elements” test
of Blockburger v. United States, 284 U. S. 299, is rejected, since that
test does not apply outside of the successive prosecution context.
Pp. 369–370.

(c) Hendricks’ ex post facto claim is similarly flawed. The Ex Post
Facto Clause pertains exclusively to penal statutes. California Dept.
of Corrections v. Morales, 514 U. S. 499, 505. Since the Act is not
punishment, its application does not raise ex post facto concerns.
Moreover, the Act clearly does not have retroactive effect. It does not
criminalize conduct legal before its enactment or deprive Hendricks
of any defense that was available to him at the time of his crimes.
Pp. 370–371.

259 Kan. 246, 912 P. 2d 129, reversed.

Thomas, J., delivered the opinion of the Court, in which Rehnquist,
C. J., and O’Connor, Scalia, and Kennedy, JJ., joined. Kennedy, J.,
filed a concurring opinion, post, p. 371. Breyer, J., filed a dissenting
opinion, in which Stevens and Souter, JJ., joined, and in which Gins-
burg, J., joined as to Parts II and III, post, p. 373.

Carla J. Stovall, Attorney General of Kansas, argued the
cause for the petitioner in No. 95–1649 and respondent in
No. 95–9075. With her on the briefs were Stephen R. Mc-
Allister, Special Assistant Attorney General, Bernard
Nash, James van R. Springer, and Laura B. Feigin.

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349Cite as: 521 U. S. 346 (1997)

Counsel

Thomas J. Weilert argued the cause for Hendricks in
both cases. With him on the briefs were James W. Ellis
and David Gottlieb.†

†Briefs of amici curiae urging reversal were filed for the State of
Washington et al. by Christine O. Gregoire, Attorney General of Wash-
ington, and Sarah Blackman Sappington, Assistant Attorney General,
Charles F. C. Ruff, Corporation Counsel of the District of Columbia, Sebas-
tian Aloot, Acting Attorney General of the Northern Mariana Islands,
and by the Attorneys General for their respective jurisdictions as follows:
Jeff Sessions of Alabama, Malaetasi Togafu of American Samoa, Grant
Woods of Arizona, Winston Bryant of Arkansas, Daniel E. Lungren of
California, Gale A. Norton of Colorado, M. Jane Brady of Delaware, Rob-
ert A. Butterworth of Florida, Calvin E. Holloway, Sr., of Guam, Margery
S. Bronster of Hawaii, Alan G. Lance of Idaho, James E. Ryan of Illinois,
Pamela Fanning Carter of Indiana, Thomas J. Miller of Iowa, A. B. Chan-
dler III of Kentucky, Richard P. Ieyoub of Louisiana, J. Joseph Curran,
Jr., of Maryland, Hubert H. Humphrey III of Minnesota, Mike Moore
of Mississippi, Jeremiah W. (Jay) Nixon of Missouri, Joseph P. Mazurek
of Montana, Don Stenberg of Nebraska, Frankie Sue Del Papa of Nevada,
Jeffrey R. Howard of New Hampshire, Peter Verniero of New Jersey, Tom
Udall of New Mexico, Dennis C. Vacco of New York, Michael F. Easley
of North Carolina, Heidi Heitkamp of North Dakota, Betty D. Mont-
gomery of Ohio, W. A. Drew Edmondson of Oklahoma, Thomas W. Corbett,
Jr., of Pennsylvania, Pedro R. Pierluisi of Puerto Rico, Jeffrey B. Pine
of Rhode Island, Charles Molony Condon of South Carolina, Mark W.
Barnett of South Dakota, Jan Graham of Utah, Jeffrey L. Amestoy of
Vermont, Julio A. Brady of the Virgin Islands, James S. Gilmore III of
Virginia, and William U. Hill of Wyoming; for the State of Wisconsin by
James E. Doyle, Attorney General, and Sally L. Wellman and Mary E.
Burke, Assistant Attorneys General; for the Menninger Foundation et al.
by Philip Allen Lacovara, James C. Geoly, and Robert Teir; and for the
Washington Legal Foundation et al. by Daniel J. Popeo and Richard A.
Samp.

Briefs of amici curiae urging affirmance were filed for the American
Civil Liberties Union et al. by Scott A. W. Johnson, Laura J. Buckland,
Steven R. Shapiro, Christopher A. Hansen, and Bruce Winick; for the
American Psychiatric Association by Richard G. Taranto; for the Na-
tional Association of Criminal Defense Lawyers et al. by David A. Reiser,
Jennifer P. Lyman, Barbara E. Bergman, and James F. Vano; for the
National Mental Health Association by Ira A. Burnim; for the Seattle-
King County Defender Association et al. by Robert C. Boruchowitz, Addie

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350 KANSAS v. HENDRICKS

Opinion of the Court

Justice Thomas delivered the opinion of the Court.
In 1994, Kansas enacted the Sexually Violent Predator

Act, which establishes procedures for the civil commitment
of persons who, due to a “mental abnormality” or a “person-
ality disorder,” are likely to engage in “predatory acts of
sexual violence.” Kan. Stat. Ann. § 59–29a01 et seq. (1994).
The State invoked the Act for the first time to commit Leroy
Hendricks, an inmate who had a long history of sexually mo-
lesting children, and who was scheduled for release from
prison shortly after the Act became law. Hendricks chal-
lenged his commitment on, inter alia, “substantive” due
process, double jeopardy, and ex post facto grounds. The
Kansas Supreme Court invalidated the Act, holding that its
precommitment condition of a “mental abnormality” did not
satisfy what the court perceived to be the “substantive” due
process requirement that involuntary civil commitment must
be predicated on a finding of “mental illness.” In re Hen-
dricks, 259 Kan. 246, 261, 912 P. 2d 129, 138 (1996). The
State of Kansas petitioned for certiorari. Hendricks subse-
quently filed a cross-petition in which he reasserted his fed-
eral double jeopardy and ex post facto claims. We granted
certiorari on both the petition and the cross-petition, 518
U. S. 1004 (1996), and now reverse the judgment below.

I

A

The Kansas Legislature enacted the Sexually Violent
Predator Act (Act) in 1994 to grapple with the problem of
managing repeat sexual offenders.1 Although Kansas al-

Hailstorks, John Stuart, Eric Janus, John T. Philipsborn, and Bernadette
Foley; and for the Washington State Psychiatric Association by David
A. Summers.

David B. Robbins filed a brief for the Association for the Treatment of
Sexual Abusers as amicus curiae.

1 Subsequent to Hendr icks’ commitment, the Kansas Leg islature
amended the Act in ways not relevant to this action. See, e. g., Kan. Stat.

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ready had a statute addressing the involuntary commitment
of those defined as “mentally ill,” the legislature determined
that existing civil commitment procedures were inadequate
to confront the risks presented by “sexually violent preda-
tors.” In the Act’s preamble, the legislature explained:

“[A] small but extremely dangerous group of sexually
violent predators exist who do not have a mental disease
or defect that renders them appropriate for involuntary
treatment pursuant to the [general involuntary civil
commitment statute] . . . . In contrast to persons appro-
priate for civil commitment under the [general involun-
tary civil commitment statute], sexually violent preda-
tors generally have anti-social personality features
which are unamenable to existing mental illness treat-
ment modalities and those features render them likely
to engage in sexually violent behavior. The legislature
further finds that sexually violent predators’ likelihood
of engaging in repeat acts of predatory sexual violence
is high. The existing involuntary commitment proce-
dure . . . is inadequate to address the risk these sexually
violent predators pose to society. The legislature fur-
ther finds that the prognosis for rehabilitating sexually
violent predators in a prison setting is poor, the treat-
ment needs of this population are very long term and
the treatment modalities for this population are very
different than the traditional treatment modalities for
people appropriate for commitment under the [general
involuntary civil commitment statute].” Kan. Stat.
Ann. § 59–29a01 (1994).

As a result, the legislature found it necessary to establish
“a civil commitment procedure for the long-term care and

Ann. § 59–29a03 (Supp. 1996) (changing notification period from 60 to 90
days); § 59–29a04 (requiring state attorney general to initiate commit-
ment proceedings).

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352 KANSAS v. HENDRICKS

Opinion of the Court

treatment of the sexually violent predator.” Ibid. The Act
defined a “sexually violent predator” as:

“any person who has been convicted of or charged with
a sexually violent offense and who suffers from a mental
abnormality or personality disorder which makes the
person likely to engage in the predatory acts of sexual
violence.” § 59–29a02(a).

A “mental abnormality” was defined, in turn, as a “congeni-
tal or acquired condition affecting the emotional or volitional
capacity which predisposes the person to commit sexually
violent offenses in a degree constituting such person a men-
ace to the health and safety of others.” § 59–29a02(b).

As originally structured, the Act’s civil commitment proce-
dures pertained to: (1) a presently confined person who, like
Hendricks, “has been convicted of a sexually violent offense”
and is scheduled for release; (2) a person who has been
“charged with a sexually violent offense” but has been found
incompetent to stand trial; (3) a person who has been found
“not guilty by reason of insanity of a sexually violent of-
fense”; and (4) a person found “not guilty” of a sexually vio-
lent offense because of a mental disease or defect. § 59–
29a03(a), § 22–3221 (1995).

The initial version of the Act, as applied to a currently
confined person such as Hendricks, was designed to initiate
a specific series of procedures. The custodial agency was
required to notify the local prosecutor 60 days before the
anticipated release of a person who might have met the Act’s
criteria. § 59–29a03. The prosecutor was then obligated,
within 45 days, to decide whether to file a petition in state
court seeking the person’s involuntary commitment. § 59–
29a04. If such a petition were filed, the court was to deter-
mine whether “probable cause” existed to support a finding
that the person was a “sexually violent predator” and thus
eligible for civil commitment. Upon such a determination,
transfer of the individual to a secure facility for professional
evaluation would occur. § 59–29a05. After that evaluation,

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Opinion of the Court

a trial would be held to determine beyond a reasonable doubt
whether the individual was a sexually violent predator. If
that determination were made, the person would then be
transferred to the custody of the Secretary of Social and Re-
habilitation Services (Secretary) for “control, care and treat-
ment until such time as the person’s mental abnormality or
personality disorder has so changed that the person is safe
to be at large.” § 59–29a07(a).

In addition to placing the burden of proof upon the State,
the Act afforded the individual a number of other procedural
safeguards. In the case of an indigent person, the State
was required to provide, at public expense, the assistance of
counsel and an examination by mental health care profes-
sionals. § 59–29a06. The individual also received the right
to present and cross-examine witnesses, and the opportun-
ity to review documentary evidence presented by the State.
§ 59–29a07.

Once an individual was confined, the Act required that
“[t]he involuntary detention or commitment . . . shall con-
form to constitutional requirements for care and treatment.”
§ 59–29a09. Confined persons were afforded three different
avenues of review: First, the committing court was obligated
to conduct an annual review to determine whether continued
detention was warranted. § 59–29a08. Second, the Secre-
tary was permitted, at any time, to decide that the confined
individual’s condition had so changed that release was appro-
priate, and could then authorize the person to petition for
release. § 59–29a10. Finally, even without the Secretary’s
permission, the confined person could at any time file a re-
lease petition. § 59–29a11. If the court found that the
State could no longer satisfy its burden under the initial
commitment standard, the individual would be freed from
confinement.

B

In 1984, Hendricks was convicted of taking “indecent liber-
ties” with two 13-year-old boys. After serving nearly 10
years of his sentence, he was slated for release to a halfway

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354 KANSAS v. HENDRICKS

Opinion of the Court

house. Shortly before his scheduled release, however, the
State filed a petition in state court seeking Hendricks’ civil
confinement as a sexually violent predator. On August 19,
1994, Hendricks appeared before the court with counsel and
moved to dismiss the petition on the grounds that the Act
violated various federal constitutional provisions. Although
the court reserved ruling on the Act’s constitutionality, it
concluded that there was probable cause to support a finding
that Hendricks was a sexually violent predator, and there-
fore ordered that he be evaluated at the Larned State Secu-
rity Hospital.

Hendricks subsequently requested a jury trial to deter-
mine whether he qualified as a sexually violent predator.
During that trial, Hendricks’ own testimony revealed a chill-
ing history of repeated child sexual molestation and abuse,
beginning in 1955 when he exposed his genitals to two young
girls. At that time, he pleaded guilty to indecent exposure.
Then, in 1957, he was convicted of lewdness involving a
young girl and received a brief jail sentence. In 1960, he
molested two young boys while he worked for a carnival.
After serving two years in prison for that offense, he was
paroled, only to be rearrested for molesting a 7-year-old girl.
Attempts were made to treat him for his sexual deviance,
and in 1965 he was considered “safe to be at large,” and was
discharged from a state psychiatric hospital. App. 139–144.

Shortly thereafter, however, Hendricks sexually assaulted
another young boy and girl—he performed oral sex on the
8-year-old girl and fondled the 11-year-old boy. He was
again imprisoned in 1967, but refused to participate in a sex
offender treatment program, and thus remained incarcerated
until his parole in 1972. Diagnosed as a pedophile, Hen-
dricks entered into, but then abandoned, a treatment pro-
gram. He testified that despite having received profes-
sional help for his pedophilia, he continued to harbor sexual
desires for children. Indeed, soon after his 1972 parole,
Hendricks began to abuse his own stepdaughter and stepson.
He forced the children to engage in sexual activity with him

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Opinion of the Court

over a period of approximately four years. Then, as noted
above, Hendricks was convicted of “taking indecent liber-
ties” with two adolescent boys after he attempted to fondle
them. As a result of that conviction, he was once again im-
prisoned, and was serving that sentence when he reached his
conditional release date in September 1994.

Hendricks admitted that he had repeatedly abused chil-
dren whenever he was not confined. He explained that
when he “get[s] stressed out,” he “can’t control the urge” to
molest children. Id., at 172. Although Hendricks recog-
nized that his behavior harms children, and he hoped he
would not sexually molest children again, he stated that the
only sure way he could keep from sexually abusing children
in the future was “to die.” Id., at 190. Hendricks readily
agreed with the state physician’s diagnosis that he suffers
from pedophilia and that he is not cured of the condition;
indeed, he told the physician that “treatment is bull——.”
Id., at 153, 190.

2

The jury unanimously found beyond a reasonable doubt
that Hendricks was a sexually violent predator. The trial
court subsequently determined, as a matter of state law, that
pedophilia qualifies as a “mental abnormality” as defined by

2 In addition to Hendricks’ own testimony, the jury heard from Hen-
dricks’ stepdaughter and stepson, who recounted the events surrounding
their repeated sexual abuse at Hendricks’ hands. App. 194–212. One of
the girls to whom Hendricks exposed himself in 1955 testified as well.
Id., at 191–194. The State also presented testimony from Lester Lee,
a licensed clinical social worker who specialized in treating male sexual
offenders, and Dr. Charles Befort, the chief psychologist at Larned State
Hospital. Lee testified that Hendricks had a diagnosis of personality trait
disturbance, passive-aggressive personality, and pedophilia. Id., at 219–
220. Dr. Befort testified that Hendricks suffered from pedophilia and is
likely to commit sexual offenses against children in the future if not con-
fined. Id., at 247–248. He further opined that pedophilia qualifies as a
“mental abnormality” within the Act’s definition of that term. Id., at 263–
264. Finally, Hendricks offered testimony from Dr. William S. Logan, a
forensic psychiatrist, who stated that it was not possible to predict with
any degree of accuracy the future dangerousness of a sex offender. Id.,
at 328–331.

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356 KANSAS v. HENDRICKS

Opinion of the Court

the Act, and thus ordered Hendricks committed to the Secre-
tary’s custody.

Hendricks appealed, claiming, among other things, that
application of the Act to him violated the Federal Consti-
tution’s Due Process, Double Jeopardy, and Ex Post Facto
Clauses. The Kansas Supreme Court accepted Hendricks’
due process claim. 259 Kan., at 261, 912 P. 2d, at 138. The
court declared that in order to commit a person involuntarily
in a civil proceeding, a State is required by “substantive”
due process to prove by clear and convincing evidence that
the person is both (1) mentally ill, and (2) a danger to himself
or to others. Id., at 259, 912 P. 2d, at 137. The court then
determined that the Act’s definition of “mental abnormality”
did not satisfy what it perceived to be this Court’s “mental
illness” requirement in the civil commitment context. As a
result, the court held that “the Act violates Hendricks’ sub-
stantive due process rights.” Id., at 261, 912 P. 2d, at 138.

The majority did not address Hendricks’ ex post facto or
double jeopardy claims. The dissent, however, considered
each of Hendricks’ constitutional arguments and rejected
them. Id., at 264–294, 912 P. 2d, 140–156 (Larson, J.,
dissenting).

II

A

Kansas argues that the Act’s definition of “mental abnor-
mality” satisfies “substantive” due process requirements.
We agree. Although freedom from physical restraint “has
always been at the core of the liberty protected by the Due
Process Clause from arbitrary governmental action,” Foucha
v. Louisiana, 504 U. S. 71, 80 (1992), that liberty interest is
not absolute. The Court has recognized that an individual’s
constitutionally protected interest in avoiding physical re-
straint may be overridden even in the civil context:

“[T]he liberty secured by the Constitution of the United
States to every person within its jurisdiction does not

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Opinion of the Court

import an absolute right in each person to be, at all
times and in all circumstances, wholly free from re-
straint. There are manifold restraints to which every
person is necessarily subject for the common good. On
any other basis organized society could not exist with
safety to its members.” Jacobson v. Massachusetts,
197 U. S. 11, 26 (1905).

Accordingly, States have in certain narrow circumstances
provided for the forcible civil detainment of people who are
unable to control their behavior and who thereby pose a dan-
ger to the public health and safety. See, e. g., 1788 N. Y.
Laws, ch. 31 (Feb. 9, 1788) (permitting confinement of the
“furiously mad”); see also A. Deutsch, The Mentally Ill in
America (1949) (tracing history of civil commitment in the
18th and 19th centuries); G. Grob, Mental Institutions in
America: Social Policy to 1875 (1973) (discussing colonial and
early American civil commitment statutes). We have con-
sistently upheld such involuntary commitment statutes pro-
vided the confinement takes place pursuant to proper proce-
dures and evidentiary standards. See Foucha, supra, at 80;
Addington v. Texas, 441 U. S. 418, 426–427 (1979). It thus
cannot be said that the involuntary civil confinement of
a limited subclass of dangerous persons is contrary to our
understanding of ordered liberty. Cf. id., at 426.

The challenged Act unambiguously requires a finding of
dangerousness either to one’s self or to others as a prerequi-
site to involuntary confinement. Commitment proceedings
can be initiated only when a person “has been convicted of
or charged with a sexually violent offense,” and “suffers from
a mental abnormality or personality disorder which makes
the person likely to engage in the predatory acts of sexual
violence.” Kan. Stat. Ann. § 59–29a02(a) (1994). The stat-
ute thus requires proof of more than a mere predisposition to
violence; rather, it requires evidence of past sexually violent
behavior and a present mental condition that creates a likeli-
hood of such conduct in the future if the person is not inca-

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358 KANSAS v. HENDRICKS

Opinion of the Court

pacitated. As we have recognized, “[p]revious instances of
violent behavior are an important indicator of future violent
tendencies.” Heller v. Doe, 509 U. S. 312, 323 (1993); see also
Schall v. Martin, 467 U. S. 253, 278 (1984) (explaining that
“from a legal point of view there is nothing inherently un-
attainable about a prediction of future criminal conduct”).

A finding of dangerousness, standing alone, is ordinarily
not a sufficient ground upon which to justify indefinite invol-
untary commitment. We have sustained civil commitment
statutes when they have coupled proof of dangerousness
with the proof of some additional factor, such as a “mental
illness” or “mental abnormality.” See, e. g., Heller, supra,
at 314–315 (Kentucky statute permitting commitment of
“mentally retarded” or “mentally ill” and dangerous individ-
ual); Allen v. Illinois, 478 U. S. 364, 366 (1986) (Illinois statute
permitting commitment of “mentally ill” and dangerous indi-
vidual); Minnesota ex rel. Pearson v. Probate Court of Ram-
sey Cty., 309 U. S. 270, 271–272 (1940) (Minnesota statute
permitting commitment of dangerous individual with “psy-
chopathic personality”). These added statutory require-
ments serve to limit involuntary civil confinement to those
who suffer from a volitional impairment rendering them
dangerous beyond their control. The Kansas Act is plainly
of a kind with these other civil commitment statutes: It re-
quires a finding of future dangerousness, and then links that
finding to the existence of a “mental abnormality” or “per-
sonality disorder” that makes it difficult, if not impossible,
for the person to control his dangerous behavior. Kan. Stat.
Ann. § 59–29a02(b) (1994). The precommitment require-
ment of a “mental abnormality” or “personality disorder” is
consistent with the requirements of these other statutes that
we have upheld in that it narrows the class of persons eligi-
ble for confinement to those who are unable to control their
dangerousness.

Hendricks nonetheless argues that our earlier cases dic-
tate a finding of “mental illness” as a prerequisite for civil
commitment, citing Foucha and Addington. He then as-

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serts that a “mental abnormality” is not equivalent to a
“mental illness” because it is a term coined by the Kansas
Legislature, rather than by the psychiatric community.
Contrary to Hendricks’ assertion, the term “mental illness”
is devoid of any talismanic significance. Not only do “psy-
chiatrists disagree widely and frequently on what constitutes
mental illness,” Ake v. Oklahoma, 470 U. S. 68, 81 (1985), but
the Court itself has used a variety of expressions to describe
the mental condition of those properly subject to civil con-
finement. See, e. g., Addington, supra, at 425–426 (using
the terms “emotionally disturbed” and “mentally ill”); Jack-
son v. Indiana, 406 U. S. 715, 732, 737 (1972) (using the terms
“incompetency” and “insanity”); cf. Foucha, 504 U. S., at 88
(O’Connor, J., concurring in part and concurring in judg-
ment) (acknowledging State’s authority to commit a person
when there is “some medical justification for doing so”).

Indeed, we have never required state legislatures to adopt
any particular nomenclature in drafting civil commitment
statutes. Rather, we have traditionally left to legislators
the task of defining terms of a medical nature that have legal
significance. Cf. Jones v. United States, 463 U. S. 354, 365,
n. 13 (1983). As a consequence, the States have, over the
years, developed numerous specialized terms to define men-
tal health concepts. Often, those definitions do not fit pre-
cisely with the definitions employed by the medical commu-
nity. The legal definitions of “insanity” and “competency,”
for example, vary substantially from their psychiatric coun-
terparts. See, e. g., Gerard, The Usefulness of the Medical
Model to the Legal System, 39 Rutgers L. Rev. 377, 391–
394 (1987) (discussing differing purposes of legal system and
the medical profession in recognizing mental illness). Legal
definitions, however, which must “take into account such
issues as individual responsibility . . . and competency,”
need not mirror those advanced by the medical profession.
American Psychiatric Association, Diagnostic and Statistical
Manual of Mental Disorders xxiii, xxvii (4th ed. 1994).

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To the extent that the civil commitment statutes we have
considered set forth criteria relating to an individual’s inabil-
ity to control his dangerousness, the Kansas Act sets forth
comparable criteria and Hendricks’ condition doubtless satis-
fies those criteria. The mental health professionals who
evaluated Hendricks diagnosed him as suffering from pedo-
philia, a condition the psychiatric profession itself classifies
as a serious mental disorder. See, e. g., id., at 524–525, 527–
528; 1 American Psychiatric Association, Treatments of Psy-
chiatric Disorders 617–633 (1989); Abel & Rouleau, Male Sex
Offenders, in Handbook of Outpatient Treatment of Adults
271 (M. Thase, B. Edelstein, & M. Hersen eds. 1990).3 Hen-
dricks even conceded that, when he becomes “stressed out,”
he cannot “control the urge” to molest children. App. 172.
This admitted lack of volitional control, coupled with a pre-
diction of future dangerousness, adequately distinguishes
Hendricks from other dangerous persons who are perhaps
more properly dealt with exclusively through criminal pro-
ceedings. Hendricks’ diagnosis as a pedophile, which quali-
fies as a “mental abnormality” under the Act, thus plainly
suffices for due process purposes.

B
We granted Hendr icks’ cross-petiti on to deter mi ne

whether the Act violates the Constitution’s double jeopardy

3 We recognize, of course, that psychiatric professionals are not in com-
plete harmony in casting pedophilia, or paraphilias in general, as “mental
illnesses.” Compare Brief for American Psychiatric Association as Ami-
cus Curiae 26 with Brief for Menninger Foundation et al. as Amici Curiae
22–25. These disagreements, however, do not tie the State’s hands in
setting the bounds of its civil commitment laws. In fact, it is precisely
where such disagreement exists that legislatures have been afforded the
widest latitude in drafting such statutes. Cf. Jones v. United States, 463
U. S. 354, 365, n. 13 (1983). As we have explained regarding congressional
enactments, when a legislature “undertakes to act in areas fraught with
medical and scientific uncertainties, legislative options must be especially
broad and courts should be cautious not to rewrite legislation.” Id., at
370 (internal quotation marks and citation omitted).

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prohibition or its ban on ex post facto lawmaking. The
thrust of Hendricks’ argument is that the Act establishes
criminal proceedings; hence confinement under it necessarily
constitutes punishment. He contends that where, as here,
newly enacted “punishment” is predicated upon past conduct
for which he has already been convicted and forced to serve
a prison sentence, the Constitution’s Double Jeopardy and
Ex Post Facto Clauses are violated. We are unpersuaded
by Hendricks’ argument that Kansas has established crimi-
nal proceedings.

The categorization of a particular proceeding as civil or
criminal “is first of all a question of statutory construction.”
Allen, 478 U. S., at 368. We must initially ascertain whether
the legislature meant the statute to establish “civil” proceed-
ings. If so, we ordinarily defer to the legislature’s stated
intent. Here, Kansas’ objective to create a civil proceeding
is evidenced by its placement of the Act within the Kansas
probate code, Kan. Stat. Ann., Art. 29 (1994) (“Care and
Treatment for Mentally Ill Persons”), instead of the crimi-
nal code, as well as its description of the Act as creating a
“civil commitment procedure,” § 59–29a01 (emphasis added).
Nothing on the face of the statute suggests that the legisla-
ture sought to create anything other than a civil commitment
scheme designed to protect the public from harm.

Although we recognize that a “civil label is not always dis-
positive,” Allen, supra, at 369, we will reject the legislature’s
manifest intent only where a party challenging the statute
provides “the clearest proof ” that “the statutory scheme [is]
so punitive either in purpose or effect as to negate [the
State’s] intention” to deem it “civil,” United States v. Ward,
448 U. S. 242, 248–249 (1980). In those limited circum-
stances, we will consider the statute to have established
criminal proceedings for constitutional purposes. Hen-
dricks, however, has failed to satisfy this heavy burden.

As a threshold matter, commitment under the Act does not
implicate either of the two primary objectives of criminal

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punishment: retribution or deterrence. The Act’s purpose is
not retributive because it does not affix culpability for prior
criminal conduct. Instead, such conduct is used solely for
evidentiary purposes, either to demonstrate that a “mental
abnormality” exists or to support a finding of future danger-
ousness. We have previously concluded that an Illinois stat-
ute was nonpunitive even though it was triggered by the
commission of a sexual assault, explaining that evidence of
the prior criminal conduct was “received not to punish past
misdeeds, but primarily to show the accused’s mental condi-
tion and to predict future behavior.” Allen, supra, at 371.
In addition, the Kansas Act does not make a criminal convic-
tion a prerequisite for commitment—persons absolved of
criminal responsibility may nonetheless be subject to con-
finement under the Act. See Kan. Stat. Ann. § 59–29a03(a)
(1994). An absence of the necessary criminal responsibility
suggests that the State is not seeking retribution for a past
misdeed. Thus, the fact that the Act may be “tied to crimi-
nal activity” is “insufficient to render the statut[e] punitive.”
United States v. Ursery, 518 U. S. 267 (1996).

Moreover, unlike a criminal statute, no finding of scienter
is required to commit an individual who is found to be a sexu-
ally violent predator; instead, the commitment determination
is made based on a “mental abnormality” or “personality dis-
order” rather than on one’s criminal intent. The existence
of a scienter requirement is customarily an important ele-
ment in distinguishing criminal from civil statutes. See
Kennedy v. Mendoza-Martinez, 372 U. S. 144, 168 (1963).
The absence of such a requirement here is evidence that con-
finement under the statute is not intended to be retributive.

Nor can it be said that the legislature intended the Act to
function as a deterrent. Those persons committed under
the Act are, by definition, suffering from a “mental abnor-
mality” or a “personality disorder” that prevents them from
exercising adequate control over their behavior. Such per-
sons are therefore unlikely to be deterred by the threat of

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confinement. And the conditions surrounding that con-
finement do not suggest a punitive purpose on the State’s
part. The State has represented that an individual confined
under the Act is not subject to the more restrictive condi-
tions placed on state prisoners, but instead experiences es-
sentially the same conditions as any involuntarily committed
patient in the state mental institution. App. 50–56, 59–60.
Because none of the parties argues that people institutional-
ized under the Kansas general civil commitment statute are
subject to punitive conditions, even though they may be in-
voluntarily confined, it is difficult to conclude that persons
confined under this Act are being “punished.”

Although the civil commitment scheme at issue here does
involve an affirmative restraint, “the mere fact that a person
is detained does not inexorably lead to the conclusion that
the government has imposed punishment.” United States
v. Salerno, 481 U. S. 739, 746 (1987). The State may take
measures to restrict the freedom of the dangerously men-
tally ill. This is a legitimate nonpunitive governmental ob-
jective and has been historically so regarded. Cf. id., at 747.
The Court has, in fact, cited the confinement of “mentally
unstable individuals who present a danger to the public” as
one classic example of nonpunitive detention. Id., at 748–
749. If detention for the purpose of protecting the commu-
nity from harm necessarily constituted punishment, then all
involuntary civil commitments would have to be considered
punishment. But we have never so held.

Hendricks focuses on his confinement’s potentially indefi-
nite duration as evidence of the State’s punitive intent.
That focus, however, is misplaced. Far from any punitive
objective, the confinement’s duration is instead linked to the
stated purposes of the commitment, namely, to hold the per-
son until his mental abnormality no longer causes him to be
a threat to others. Cf. Jones, 463 U. S., at 368 (noting with
approval that “because it is impossible to predict how long
it will take for any given individual to recover [from insan-

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364 KANSAS v. HENDRICKS

Opinion of the Court

ity]—or indeed whether he will ever recover—Congress has
chosen . . . to leave the length of commitment indeterminate,
subject to periodic review of the patient’s suitability for re-
lease”). If, at any time, the confined person is adjudged
“safe to be at large,” he is statutorily entitled to immediate
release. Kan. Stat. Ann. § 59–29a07 (1994).

Furthermore, commitment under the Act is only poten-
tially indefinite. The maximum amount of time an individ-
ual can be incapacitated pursuant to a single judicial proceed-
ing is one year. § 59–29a08. If Kansas seeks to continue
the detention beyond that year, a court must once again de-
termine beyond a reasonable doubt that the detainee satis-
fies the same standards as required for the initial confine-
ment. Ibid. This requirement again demonstrates that
Kansas does not intend an individual committed pursuant to
the Act to remain confined any longer than he suffers from
a mental abnormality rendering him unable to control his
dangerousness.

Hendricks next contends that the State’s use of procedural
safeguards traditionally found in criminal trials makes the
proceedings here criminal rather than civil. In Allen, we
confronted a similar argument. There, the petitioner
“place[d] great reliance on the fact that proceedings under
the Act are accompanied by procedural safeguards usually
found in criminal trials” to argue that the proceedings were
civil in name only. 478 U. S., at 371. We rejected that ar-
gument, however, explaining that the State’s decision “to
provide some of the safeguards applicable in criminal trials
cannot itself turn these proceedings into criminal prosecu-
tions.” Id., at 372. The numerous procedural and eviden-
tiary protections afforded here demonstrate that the Kansas
Legislature has taken great care to confine only a narrow
class of particularly dangerous individuals, and then only
after meeting the strictest procedural standards. That
Kansas chose to afford such procedural protections does not

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transform a civil commitment proceeding into a criminal
prosecution.

Finally, Hendricks argues that the Act is necessarily pu-
nitive because it fails to offer any legitimate “treatment.”
Without such treatment, Hendricks asserts, confinement
under the Act amounts to little more than disguised punish-
ment. Hendricks’ argument assumes that treatment for his
condition is available, but that the State has failed (or re-
fused) to provide it. The Kansas Supreme Court, however,
apparently rejected this assumption, explaining:

“It is clear that the overriding concern of the legisla-
ture is to continue the segregation of sexually violent
offenders from the public. Treatment with the goal of
reintegrating them into society is incidental, at best.
The record reflects that treatment for sexually violent
predators is all but nonexistent. The legislature con-
cedes that sexually violent predators are not amenable
to treatment under [the existing Kansas involuntary
commitment statute]. If there is nothing to treat under
[that statute], then there is no mental illness. In that
light, the provisions of the Act for treatment appear
somewhat disingenuous.” 259 Kan., at 258, 912 P. 2d,
at 136.

It is possible to read this passage as a determination that
Hendricks’ condition was untreatable under the existing
Kansas civil commitment statute, and thus the Act’s sole pur-
pose was incapacitation. Absent a treatable mental illness,
the Kansas court concluded, Hendricks could not be detained
against his will.

Accepting the Kansas court’s apparent determination that
treatment is not possible for this category of individuals does
not obligate us to adopt its legal conclusions. We have al-
ready observed that, under the appropriate circumstances
and when accompanied by proper procedures, incapacitation

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may be a legitimate end of the civil law. See Allen, supra,
at 373; Salerno, 481 U. S., at 748–749. Accordingly, the Kan-
sas court’s determination that the Act’s “overriding concern”
was the continued “segregation of sexually violent offenders”
is consistent with our conclusion that the Act establishes civil
proceedings, 259 Kan., at 258, 912 P. 2d, at 136, especially
when that concern is coupled with the State’s ancillary goal
of providing treatment to those offenders, if such is possible.
While we have upheld state civil commitment statutes that
aim both to incapacitate and to treat, see Allen, supra, we
have never held that the Constitution prevents a State from
civilly detaining those for whom no treatment is available,
but who nevertheless pose a danger to others. A State
could hardly be seen as furthering a “punitive” purpose by
involuntarily confining persons afflicted with an untreatable,
highly contagious disease. Accord, Compagnie Francaise
de Navigation a Vapeur v. Louisiana Bd. of Health, 186
U. S. 380 (1902) (permitting involuntary quarantine of per-
sons suffering from communicable diseases). Similarly, it
would be of little value to require treatment as a precondi-
tion for civil confinement of the dangerously insane when
no acceptable treatment existed. To conclude otherwise
would obligate a State to release certain confined individuals
who were both mentally ill and dangerous simply because
they could not be successfully treated for their afflictions.
Cf. Greenwood v. United States, 350 U. S. 366, 375 (1956)
(“The fact that at present there may be little likelihood of
recovery does not defeat federal power to make this initial
commitment of the petitioner”); O’Connor v. Donaldson, 422
U. S. 563, 584 (1975) (Burger, C. J., concurring) (“[I]t remains
a stubborn fact that there are many forms of mental illness
which are not understood, some which are untreatable in the
sense that no effective therapy has yet been discovered for
them, and that rates of ‘cure’ are generally low”).

Alternatively, the Kansas Supreme Court’s opinion can be
read to conclude that Hendricks’ condition is treatable, but

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that treatment was not the State’s “overriding concern,” and
that no treatment was being provided (at least at the time
Hendricks was committed). 259 Kan., at 258, 912 P. 2d, at
136. See also ibid. (“It is clear that the primary objective
of the Act is to continue incarceration and not to provide
treatment”). Even if we accept this determination that the
provision of treatment was not the Kansas Legislature’s
“overriding ” or “primary” purpose in passing the Act, this
does not rule out the possibility that an ancillary purpose of
the Act was to provide treatment, and it does not require us
to conclude that the Act is punitive. Indeed, critical lan-
guage in the Act itself demonstrates that the Secretary,
under whose custody sexually violent predators are com-
mitted, has an obligation to provide treatment to individuals
like Hendricks. § 59–29a07(a) (“If the court or jury de-
termines that the person is a sexually violent predator, the
person shall be committed to the custody of the secretary
of social and rehabilitation services for control, care and
treatment until such time as the person’s mental abnormality
or personality disorder has so changed that the person is safe
to be at large” (emphasis added)). Other of the Act’s sec-
tions echo this obligation to provide treatment for committed
persons. See, e. g., § 59–29a01 (establishing civil commit-
ment procedure “for the long-term care and treatment of
the sexually violent predator”); § 59–29a09 (requiring the
confinement to “conform to constitutional requirements for
care and treatment”). Thus, as in Allen, “the State has a
statutory obligation to provide ‘care and treatment for
[persons adjudged sexually dangerous] designed to effect
recovery,’ ” 478 U. S., at 369 (quoting Ill. Rev. Stat., ch. 38,
¶ 105–8 (1985)), and we may therefore conclude that “the
State has . . . provided for the treatment of those it commits,”
478 U. S., at 370.

Although the treatment program initially offered Hen-
dricks may have seemed somewhat meager, it must be re-
membered that he was the first person committed under the

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Opinion of the Court

Act. That the State did not have all of its treatment proce-
dures in place is thus not surprising. What is significant,
however, is that Hendricks was placed under the supervision
of the Kansas Department of Health and Social and Re-
habilitative Services, housed in a unit segregated from the
general prison population and operated not by employees
of the Department of Corrections, but by other trained in-
dividuals.4 And, before this Court, Kansas declared “[a]b-
solutely” that persons committed under the Act are now
receiving in the neighborhood of “31-1⁄2 hours of treatment
per week.” Tr. of Oral Arg. 14–15, 16.5

Where the State has “disavowed any punitive intent”; lim-
ited confinement to a small segment of particularly danger-
ous individuals; provided strict procedural safeguards; di-
rected that confined persons be segregated from the general
prison population and afforded the same status as others who
have been civilly committed; recommended treatment if such
is possible; and permitted immediate release upon a showing

4 We have explained that the States enjoy wide latitude in developing
treatment regimens. Youngberg v. Romeo, 457 U. S. 307, 317 (1982) (ob-
serving that the State “has considerable discretion in determining the na-
ture and scope of its responsibilities”). In Allen v. Illinois, 478 U. S. 364
(1986), for example, we concluded that “the State serves its purpose of
treating rather than punishing sexually dangerous persons by committing
them to an institution expressly designed to provide psychiatric care and
treatment.” Id., at 373 (emphasis deleted). By this measure, Kansas has
doubtless satisfied its obligation to provide available treatment.

5 Indeed, we have been informed that in an August 28, 1995, hearing on
Hendricks’ petition for state habeas corpus relief, the trial court, over
admittedly conflicting testimony, ruled: “[T]he allegation that no treat-
ment is being provided to any of the petitioners or other persons com-
mitted to the program designated as a sexual predator treatment program
is not true. I find that they are receiving treatment.” App. 453–454.
Thus, to the extent that treatment is available for Hendricks’ condition,
the State now appears to be providing it. By furnishing such treatment,
the Kansas Legislature has indicated that treatment, if possible, is at least
an ancillary goal of the Act, which easily satisfies any test for determining
that the Act is not punitive.

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that the individual is no longer dangerous or mentally im-
paired, we cannot say that it acted with punitive intent. We
therefore hold that the Act does not establish criminal pro-
ceedings and that involuntary confinement pursuant to the
Act is not punitive. Our conclusion that the Act is nonpuni-
tive thus removes an essential prerequisite for both Hen-
dricks’ double jeopardy and ex post facto claims.

1

The Double Jeopardy Clause provides: “[N]or shall any
person be subject for the same offence to be twice put in
jeopardy of life or limb.” Although generally understood to
preclude a second prosecution for the same offense, the
Court has also interpreted this prohibition to prevent the
State from “punishing twice, or attempting a second time to
punish criminally, for the same offense.” Witte v. United
States, 515 U. S. 389, 396 (1995) (emphasis and internal quota-
tion marks omitted). Hendricks argues that, as applied to
him, the Act violates double jeopardy principles because his
confinement under the Act, imposed after a conviction and a
term of incarceration, amounted to both a second prosecution
and a second punishment for the same offense. We disagree.

Because we have determined that the Kansas Act is civil
in nature, initiation of its commitment proceedings does not
constitute a second prosecution. Cf. Jones v. United States,
463 U. S. 354 (1983) (permitting involuntary civil commit-
ment after verdict of not guilty by reason of insanity).
Moreover, as commitment under the Act is not tantamount
to “punishment,” Hendricks’ involuntary detention does not
violate the Double Jeopardy Clause, even though that con-
finement may follow a prison term. Indeed, in Baxstrom v.
Herold, 383 U. S. 107 (1966), we expressly recognized that
civil commitment could follow the expiration of a prison term
without offending double jeopardy principles. We reasoned
that “there is no conceivable basis for distinguishing the
commitment of a person who is nearing the end of a penal

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Opinion of the Court

term from all other civil commitments.” Id., at 111–112. If
an individual otherwise meets the requirements for involun-
tary civil commitment, the State is under no obligation to
release that individual simply because the detention would
follow a period of incarceration.

Hendricks also argues that even if the Act survives the
“multiple punishments” test, it nevertheless fails the “same
elements” test of Blockburger v. United States, 284 U. S. 299
(1932). Under Blockburger, “where the same act or transac-
tion constitutes a violation of two distinct statutory provi-
sions, the test to be applied to determine whether there are
two offenses or only one, is whether each provision requires
proof of a fact which the other does not.” Id., at 304. The
Blockburger test, however, simply does not apply outside of
the successive prosecution context. A proceeding under the
Act does not define an “offense,” the elements of which can
be compared to the elements of an offense for which the per-
son may previously have been convicted. Nor does the Act
make the commission of a specified “offense” the basis for
invoking the commitment proceedings. Instead, it uses a
prior conviction (or previously charged conduct) for eviden-
tiary purposes to determine whether a person suffers from
a “mental abnormality” or “personality disorder” and also
poses a threat to the public. Accordingly, we are unper-
suaded by Hendricks’ novel application of the Blockburger
test and conclude that the Act does not violate the Double
Jeopardy Clause.

2

Hendricks’ ex post facto claim is similarly flawed. The Ex
Post Facto Clause, which “ ‘forbids the application of any new
punitive measure to a crime already consummated,’ ” has
been interpreted to pertain exclusively to penal statutes.
California Dept. of Corrections v. Morales, 514 U. S. 499,
505 (1995) (quoting Lindsey v. Washington, 301 U. S. 397, 401
(1937)). As we have previously determined, the Act does
not impose punishment; thus, its application does not raise

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Kennedy, J., concurring

ex post facto concerns. Moreover, the Act clearly does not
have retroactive effect. Rather, the Act permits involun-
tary confinement based upon a determination that the person
currently both suffers from a “mental abnormality” or “per-
sonality disorder” and is likely to pose a future danger to the
public. To the extent that past behavior is taken into ac-
count, it is used, as noted above, solely for evidentiary pur-
poses. Because the Act does not criminalize conduct legal
before its enactment, nor deprive Hendricks of any defense
that was available to him at the time of his crimes, the Act
does not violate the Ex Post Facto Clause.

III

We hold that the Kansas Sexually Violent Predator Act
comports with due process requirements and neither runs
afoul of double jeopardy principles nor constitutes an exer-
cise in impermissible ex post facto lawmaking. Accordingly,
the judgment of the Kansas Supreme Court is reversed.

It is so ordered.

Justice Kennedy, concurring.
I join the opinion of the Court in full and add these addi-

tional comments.
Though other issues were argued to us, as the action has

matured it turns on whether the Kansas statute is an ex post
facto law. A law enacted after commission of the offense
and which punishes the offense by extending the term of
confinement is a textbook example of an ex post facto law.
If the object or purpose of the Kansas law had been to pro-
vide treatment but the treatment provisions were adopted
as a sham or mere pretext, there would have been an indica-
tion of the forbidden purpose to punish. The Court’s opinion
gives a full and complete explanation why an ex post facto
challenge based on this contention cannot succeed in the ac-
tion before us. All this, however, concerns Hendricks alone.
My brief, further comment is to caution against dangers in-

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372 KANSAS v. HENDRICKS

Kennedy, J., concurring

herent when a civil confinement law is used in conjunction
with the criminal process, whether or not the law is given
retroactive application.

It seems the dissent, too, would validate the Kansas stat-
ute as to persons who committed the crime after its enact-
ment, and it might even validate the statute as to Hendricks,
assuming a reasonable level of treatment. As all Members
of the Court seem to agree, then, the power of the State to
confine persons who, by reason of a mental disease or mental
abnormality, constitute a real, continuing, and serious danger
to society is well established. Addington v. Texas, 441 U. S.
418, 426–427 (1979). Confinement of such individuals is per-
mitted even if it is pursuant to a statute enacted after the
crime has been committed and the offender has begun serv-
ing, or has all but completed serving, a penal sentence, pro-
vided there is no object or purpose to punish. See Bax-
strom v. Herold, 383 U. S. 107, 111–112 (1966). The Kansas
law, with its attendant protections, including yearly review
and review at any time at the instance of the person confined,
is within this pattern and tradition of civil confinement. In
this action, the mental abnormality—pedophilia—is at least
described in the DSM–IV. American Psychiatric Associa-
tion, Diagnostic and Statistical Manual of Mental Disorders
524–525, 527–528 (4th ed. 1994).

Notwithstanding its civil attributes, the practical effect of
the Kansas law may be to impose confinement for life. At
this stage of medical knowledge, although future treatments
cannot be predicted, psychiatrists or other professionals en-
gaged in treating pedophilia may be reluctant to find meas-
urable success in treatment even after a long period and may
be unable to predict that no serious danger will come from
release of the detainee.

A common response to this may be, “A life term is exactly
what the sentence should have been anyway,” or, in the
words of a Kansas task force member, “SO BE IT.” Testi-
mony of Jim Blaufuss, App. 503. The point, however, is not

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how long Hendricks and others like him should serve a crimi-
nal sentence. With his criminal record, after all, a life term
may well have been the only sentence appropriate to protect
society and vindicate the wrong. The concern instead is
whether it is the criminal system or the civil system which
should make the decision in the first place. If the civil sys-
tem is used simply to impose punishment after the State
makes an improvident plea bargain on the criminal side, then
it is not performing its proper function. These concerns
persist whether the civil confinement statute is put on the
books before or after the offense. We should bear in mind
that while incapacitation is a goal common to both the crimi-
nal and civil systems of confinement, retribution and general
deterrence are reserved for the criminal system alone.

On the record before us, the Kansas civil statute conforms
to our precedents. If, however, civil confinement were to
become a mechanism for retribution or general deterrence,
or if it were shown that mental abnormality is too imprecise
a category to offer a solid basis for concluding that civil de-
tention is justified, our precedents would not suffice to vali-
date it.

Justice Breyer, with whom Justice Stevens and Jus-
tice Souter join, and with whom Justice Ginsburg joins
as to Parts II and III, dissenting.

I agree with the majority that the Kansas Sexually Violent
Predator Act’s “definition of ‘mental abnormality’ ” satisfies
the “substantive” requirements of the Due Process Clause.
Ante, at 356. Kansas, however, concedes that Hendricks’
condition is treatable; yet the Act did not provide Hendricks
(or others like him) with any treatment until after his re-
lease date from prison and only inadequate treatment there-
after. These, and certain other, special features of the Act
convince me that it was not simply an effort to commit Hen-
dricks civilly, but rather an effort to inflict further punish-
ment upon him. The Ex Post Facto Clause therefore pro-

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374 KANSAS v. HENDRICKS

Breyer, J., dissenting

hibits the Act’s application to Hendricks, who committed
his crimes prior to its enactment.

I

I begin with the area of agreement. This Court has held
that the civil commitment of a “mentally ill” and “dangerous”
person does not automatically violate the Due Process
Clause provided that the commitment takes place pursuant
to proper procedures and evidentiary standards. See Fou-
cha v. Louisiana, 504 U. S. 71, 80 (1992); Addington v. Texas,
441 U. S. 418, 426–427 (1979). The Kansas Supreme Court,
however, held that the Due Process Clause forbids applica-
tion of the Act to Hendricks for “substantive” reasons, i. e.,
irrespective of the procedures or evidentiary standards used.
The court reasoned that Kansas had not satisfied the “men-
tally ill” requirement of the Due Process Clause because
Hendricks was not “mentally ill.” In re Hendricks, 259 Kan.
246, 260–261, 912 P. 2d 129, 137–138 (1996). Moreover, Kan-
sas had not satisfied what the court believed was an addi-
tional “substantive due process” requirement, namely, the
provision of treatment. Id., at 257–258, 912 P. 2d, at 136. I
shall consider each of these matters briefly.

A

In my view, the Due Process Clause permits Kansas to
classify Hendricks as a mentally ill and dangerous person for
civil commitment purposes. Allen v. Illinois, 478 U. S. 364,
370–371, 373–375 (1986). I agree with the majority that the
Constitution gives States a degree of leeway in making this
kind of determination. Ante, at 359; Foucha, supra, at 87
(O’Connor, J., concurring in part and concurring in judg-
ment); Jones v. United States, 463 U. S. 354, 365, n. 13 (1983).
But, because I do not subscribe to all of its reasoning, I shall
set forth three sets of circumstances that, taken together,
convince me that Kansas has acted within the limits that the
Due Process Clause substantively sets.

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Breyer, J., dissenting

First, the psychiatric profession itself classifies the kind of
problem from which Hendricks suffers as a serious mental
disorder. E. g., American Psychiatric Assn., Diagnostic and
Statistical Manual of Mental Disorders 524–525, 527–528 (4th
ed. 1994) (describing range of paraphilias and discussing how
stress aggravates pedophilic behavior); Abel & Rouleau,
Male Sex Offenders, in Handbook of Outpatient Treatment
of Adults 271 (M. Thase, B. Edelstein, & M. Hersen eds.
1990). I concede that professionals also debate whether or
not this disorder should be called a mental “illness.” See
R. Slovenko, Psychiatry and Criminal Culpability 57 (1995)
(citing testimony that paraphilias are not mental illnesses);
Schopp & Sturgis, Sexual Predators and Legal Mental Ill-
ness for Civil Commitment, 13 Behav. Sci. & The Law 437,
451–452 (1995) (same). Compare Brief for American Psy-
chiatric Association as Amicus Curiae 26 (mental illness
requirement not satisfied) with Brief for Menninger Clinic
et al. as Amici Curiae 22–25 (requirement is satisfied). But
the very presence and vigor of this debate is important.
The Constitution permits a State to follow one reasonable
professional view, while rejecting another. See Addington
v. Texas, supra, at 431. The psychiatric debate, therefore,
helps to inform the law by setting the bounds of what is
reasonable, but it cannot here decide just how States must
write their laws within those bounds. See Jones, supra, at
365, n. 13.

Second, Hendricks’ abnormality does not consist simply of
a long course of antisocial behavior, but rather it includes a
specific, serious, and highly unusual inability to control his
actions. (For example, Hendricks testified that, when he
gets “stressed out,” he cannot “control the urge” to molest
children, see ante, at 355.) The law traditionally has consid-
ered this kind of abnormality akin to insanity for purposes
of confinement. See, e. g., Minnesota ex rel. Pearson v. Pro-
bate Court of Ramsey Cty., 309 U. S. 270, 274 (1940) (uphold-
ing against a due process challenge the civil confinement of

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Breyer, J., dissenting

a dangerous person where the danger flowed from an “ ‘utter
lack of power to control . . . sexual impulses’ ”) (quoting State
ex rel. Pearson v. Probate Court of Ramsey Cty., 205 Minn.
545, 555, 287 N. W. 297, 302 (1939)); 1788 N. Y. Laws, ch. 31
(permitting confinement of those who are “furiously mad”);
In re Oakes, 8 Law Rep. 122, 125 (Mass. 1845) (Shaw, C. J.);
A. Deutsch, The Mentally Ill in America 419–420 (1949)
(tracing history of commitment of furiously mad people in
18th and 19th centuries); Dershowitz, The Origins of Preven-
tative Confinement in Anglo-American Law—Part II: The
American Experience, 43 U. Cin. L. Rev. 781 (1974). Indeed,
the notion of an “irresistible impulse” often has helped to
shape criminal law’s insanity defense and to inform the re-
lated recommendations of legal experts as they seek to trans-
late the insights of mental health professionals into workable
legal rules. See also American Law Institute, Model Penal
Code § 4.01 (insanity defense, in part, rests on inability “to
conform . . . conduct to the requirements of law”); A. Gold-
stein, The Insanity Defense 67–79 (1967) (describing “irre-
sistible impulse” test).

Third, Hendricks’ mental abnormality also makes him dan-
gerous. Hendricks “has been convicted of . . . a sexually
violent offense,” and a jury found that he “suffers from a
mental abnormality . . . which makes” him “likely to engage”
in similar “acts of sexual violence” in the future. Kan. Stat.
Ann. §§ 59–29a02, 59–29a03 (1994). The evidence at trial fa-
vored the State. Dr. Befort, for example, explained why
Hendricks was likely to commit further acts of sexual vio-
lence if released. See, e. g., App. 248–254. And Hendricks’
own testimony about what happens when he gets “stressed
out” confirmed Dr. Befort’s diagnosis.

Because (1) many mental health professionals consider pe-
dophilia a serious mental disorder; and (2) Hendricks suffers
from a classic case of irresistible impulse, namely, he is so
afflicted with pedophilia that he cannot “control the urge” to
molest children; and (3) his pedophilia presents a serious

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Breyer, J., dissenting

danger to those children, I believe that Kansas can classify
Hendricks as “mentally ill” and “dangerous” as this Court
used those terms in Foucha.

The Kansas Supreme Court’s contrary conclusion rested
primarily upon that court’s view that Hendricks would not
qualify for civil commitment under Kansas’ own state civil
commitment statute. The issue before us, however, is one
of constitutional interpretation. The Constitution does not
require Kansas to write all of its civil commitment rules in
a single statute or forbid it to write two separate statutes
each covering somewhat different classes of committable in-
dividuals. Moreover, Hendricks apparently falls outside the
scope of the Kansas general civil commitment statute be-
cause that statute permits confinement only of those who
“lac[k] capacity to make an informed decision concerning
treatment.” Kan. Stat. Ann. § 59–2902(h) (1994). The stat-
ute does not tell us why it imposes this requirement. Ca-
pacity to make an informed decision about treatment is not
always or obviously incompatible with severe mental illness.
Neither Hendricks nor his amici point to a uniform body of
professional opinion that says as much, and we have not
found any. See, e. g., American Psychiatric Assn., Guide-
lines for Legislation on the Psychiatric Hospitalization of
Adults, 140 Am. J. Psychiatry 672, 673 (1983); Stromberg &
Stone, A Model State Law on Civil Commitment of the Men-
tally Ill, 20 Harv. J. Legis. 275, 301–302 (1983); DeLand &
Borenstein, Medicine Court, II, Rivers in Practice, 147 Am.
J. Psychiatry 38 (1990). Consequently, the boundaries of the
Federal Constitution and those of Kansas’ general civil com-
mitment statute are not congruent.

B

The Kansas Supreme Court also held that the Due Process
Clause requires a State to provide treatment to those whom
it civilly confines (as “mentally ill” and “dangerous”). It
found that Kansas did not provide Hendricks with significant

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treatment. And it concluded that Hendricks’ confinement
violated the Due Process Clause for this reason as well.

This case does not require us to consider whether the Due
Process Clause always requires treatment—whether, for ex-
ample, it would forbid civil confinement of an untreatable
mentally ill, dangerous person. To the contrary, Kansas ar-
gues that pedophilia is an “abnormality” or “illness” that can
be treated. See Tr. of Oral Arg. 12 (Kansas Attorney Gen-
eral, in response to the question “you’re claiming that there
is some treatability . . . ?” answering “[a]bsolutely”); Brief
for Petitioner 42–47. Two groups of mental health profes-
sionals agree. Brief for Association for the Treatment of
Sexual Abusers as Amicus Curiae 11–12 (stating that “sex
offenders can be treated” and that “increasing evidence”
shows that “state-of-the-art treatment programs . . . signifi-
cantly reduce recidivism”); Brief for Menninger Foundation
et al. as Amici Curiae 28. Indeed, no one argues the con-
trary. Hence the legal question before us is whether the
Clause forbids Hendricks’ confinement unless Kansas pro-
vides him with treatment that it concedes is available.

Nor does anyone argue that Kansas somehow could have
violated the Due Process Clause’s treatment concerns had it
provided Hendricks with the treatment that is potentially
available (and I do not see how any such argument could
succeed). Rather, the basic substantive due process treat-
ment question is whether that Clause requires Kansas to
provide treatment that it concedes is potentially available to
a person whom it concedes is treatable. This same question
is at the heart of my discussion of whether Hendricks’ con-
finement violates the Constitution’s Ex Post Facto Clause.
See infra, at 383–395. For that reason, I shall not consider
the substantive due process treatment question separately,
but instead shall simply turn to the Ex Post Facto Clause
discussion. As Justice Kennedy points out, ante, p. 371,
some of the matters there discussed may later prove relevant
to substantive due process analysis.

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II

Kansas’ 1994 Act violates the Federal Constitution’s prohi-
bition of “any . . . ex post facto Law” if it “inflicts” upon
Hendricks “a greater punishment” than did the law “annexed
to” his “crime[s]” when he “committed” those crimes in 1984.
Calder v. Bull, 3 Dall. 386, 390 (1798) (opinion of Chase, J.);
U. S. Const., Art. I, § 10. The majority agrees that the
Clause “ ‘forbids the application of any new punitive measure
to a crime already consummated.’ ” California Dept. of
Corrections v. Morales, 514 U. S. 499, 505 (1995) (citation
omitted; emphasis added). Ante, at 370–371. But it finds
the Act is not “punitive.” With respect to that basic ques-
tion, I disagree with the majority.

Certain resemblances between the Act’s “civil commit-
ment” and traditional criminal punishments are obvious.
Like criminal imprisonment, the Act’s civil commitment
amounts to “secure” confinement, Kan. Stat. Ann. § 59–
29a07(a) (1994), and “incarceration against one’s will,” In re
Gault, 387 U. S. 1, 50 (1967). See Testimony of Terry Davis,
SRS Director of Quality Assurance, App. 52–54, 78–81 (con-
finement takes place in the psychiatric wing of a prison hos-
pital where those whom the Act confines and ordinary pris-
oners are treated alike). Cf. Browning-Ferris Industries of
Vt., Inc. v. Kelco Disposal, Inc., 492 U. S. 257, 298 (1989)
(O’Connor, J., concurring in part and dissenting in part).
In addition, a basic objective of the Act is incapacitation,
which, as Blackstone said in describing an objective of crimi-
nal law, is to “depriv[e] the party injuring of the power to do
future mischief.” 4 W. Blackstone, Commentaries *11–*12
(incapacitation is one important purpose of criminal punish-
ment); see also Foucha, 504 U. S., at 99 (Kennedy, J., dis-
senting) (“Incapacitation for the protection of society is not
an unusual ground for incarceration”); United States v.
Brown, 381 U. S. 437, 458 (1965) (“Punishment serves several
purposes: retributive, rehabilitative, deterrent—and preven-
tative. One of the reasons society imprisons those convicted

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of crimes is to keep them from inflicting future harm, but
that does not make imprisonment any the less punishment”);
1 W. LaFave & A. Scott, Substantive Criminal Law § 1.5,
p. 32 (1986); 18 U. S. C. § 3553(a); United States Sentencing
Guidelines, Guidelines Manual, ch. 1, pt. A (Nov. 1995).

Moreover, the Act, like criminal punishment, imposes its
confinement (or sanction) only upon an individual who has
previously committed a criminal offense. Kan. Stat. Ann.
§§ 59–29a02(a), 59–29a03(a) (1994). Cf. Department of Reve-
nue of Mont. v. Kurth Ranch, 511 U. S. 767, 781 (1994) (fact
that a tax on marijuana was “conditioned on the commission
of a crime” is “ ‘significant of [its] penal and prohibitory in-
tent’ ” (citation omitted)); Lipke v. Lederer, 259 U. S. 557,
561–562 (1922). And the Act imposes that confinement
through the use of persons (county prosecutors), procedural
guarantees (trial by jury, assistance of counsel, psychiatric
evaluations), and standards (“beyond a reasonable doubt”)
traditionally associated with the criminal law. Kan. Stat.
Ann. §§ 59–29a06, 59–29a07 (1994).

These obvious resemblances by themselves, however, are
not legally sufficient to transform what the Act calls “civil
commitment” into a criminal punishment. Civil commit-
ment of dangerous, mentally ill individuals by its very nature
involves confinement and incapacitation. Yet “civil commit-
ment,” from a constitutional perspective, nonetheless re-
mains civil. Allen v. Illinois, 478 U. S., at 369–370. Nor
does the fact that criminal behavior triggers the Act make
the critical difference. The Act’s insistence upon a prior
crime, by screening out those whose past behavior does not
concretely demonstrate the existence of a mental problem or
potential future danger, may serve an important noncriminal
evidentiary purpose. Neither is the presence of criminal
law-type procedures determinative. Those procedures can
serve an important purpose that in this context one might
consider noncriminal, namely, helping to prevent judgmental

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mistakes that would wrongly deprive a person of important
liberty. Id., at 371–372.

If these obvious similarities cannot by themselves prove
that Kansas’ “civil commitment” statute is criminal, neither
can the word “civil” written into the statute, § 59–29a01, by
itself prove the contrary. This Court has said that only the
“clearest proof ” could establish that a law the legislature
called “civil” was, in reality, a “punitive” measure. United
States v. Ward, 448 U. S. 242, 248–249 (1980). But the Court
has also reiterated that a “civil label is not always disposi-
tive,” Allen v. Illinois, supra, at 369; it has said that in close
cases the label is “ ‘not of paramount importance,’ ” Kurth
Ranch, supra, at 777 (citation omitted); and it has looked
behind a “civil” label fairly often, e. g., United States v.
Halper, 490 U. S. 435, 447 (1989).

In this circumstance, with important features of the Act
pointing in opposite directions, I would place particular im-
portance upon those features that would likely distinguish
between a basically punitive and a basically nonpunitive pur-
pose. United States v. Ursery, 518 U. S. 267, 278 (1996) (ask-
ing whether a statutory scheme was so punitive “ ‘either in
purpose or effect’ ” to negate the legislature’s “ ‘intention to
establish a civil remedial mechanism’ ” (citations omitted)).
And I note that the Court, in an earlier civil commitment
case, Allen v. Illinois, 478 U. S., at 369, looked primarily to
the law’s concern for treatment as an important distinguish-
ing feature. I do not believe that Allen means that a partic-
ular law’s lack of concern for treatment, by itself, is enough
to make an incapacitative law punitive. But, for reasons I
will point out, when a State believes that treatment does
exist, and then couples that admission with a legislatively
required delay of such treatment until a person is at the end
of his jail term (so that further incapacitation is therefore
necessary), such a legislative scheme begins to look punitive.

In Allen, the Court considered whether, for Fifth Amend-
ment purposes, proceedings under an Illinois statute were

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civil or “criminal.” The Illinois statute, rather like the Kan-
sas statute here, authorized the confinement of persons who
were sexually dangerous, who had committed at least one
prior sexual assault, and who suffered from a “mental disor-
der.” Id., at 366, n. 1. The Allen Court, looking behind the
statute’s “civil commitment” label, found the statute civil—
in important part because the State had “provided for the
treatment of those it commits.” Id., at 370 (also referring
to facts that the State had “disavowed any interest in punish-
ment” and that it had “established a system under which
committed persons may be released after the briefest time
in confinement”).

In reaching this conclusion, the Court noted that the State
Supreme Court had found the proceedings “ ‘essentially
civil’ ” because the statute’s aim was to provide “ ‘treatment,
not punishment.’ ” Id., at 367 (quoting People v. Allen, 107
Ill. 2d 91, 99–101, 481 N. E. 2d 690, 694–695 (1985)). It ob-
served that the State had “a statutory obligation to provide
‘care and treatment . . . designed to effect recovery’ ” in a
“facility set aside to provide psychiatric care.” 478 U. S., at
369 (quoting Ill. Rev. Stat., ch. 38, ¶ 105–8 (1985)). And it
referred to the State’s purpose as one of “treating rather
than punishing sexually dangerous persons.” 478 U. S., at
373; see also ibid. (“Had petitioner shown, for example, that
the confinement . . . imposes . . . a regimen which is essen-
tially identical to that imposed upon felons with no need for
psychiatric care, this might well be a different case”).

The Allen Court’s focus upon treatment, as a kind of
touchstone helping to distinguish civil from punitive pur-
poses, is not surprising, for one would expect a nonpunitive
statutory scheme to confine, not simply in order to protect,
but also in order to cure. That is to say, one would expect
a nonpunitively motivated legislature that confines because
of a dangerous mental abnormality to seek to help the indi-
vidual himself overcome that abnormality (at least insofar
as professional treatment for the abnormality exists and is

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potentially helpful, as Kansas, supported by some groups of
mental health professionals, argues is the case here, see
supra, at 378). Conversely, a statutory scheme that pro-
vides confinement that does not reasonably fit a practically
available, medically oriented treatment objective, more
likely reflects a primarily punitive legislative purpose.

Several important treatment-related factors—factors of a
kind that led the five-Member Allen majority to conclude
that the Illinois Legislature’s purpose was primarily civil,
not punitive—in this action suggest precisely the opposite.
First, the State Supreme Court here, unlike the state court
in Allen, has held that treatment is not a significant objective
of the Act. The Kansas court wrote that the Act’s purpose
is “segregation of sexually violent offenders,” with “treat-
ment” a matter that was “incidental at best.” 259 Kan., at
258, 912 P. 2d, at 136. By way of contrast, in Allen the Illi-
nois court had written that “ ‘treatment, not punishment,’ ”
was “the aim of the statute.” Allen, supra, at 367 (quoting
People v. Allen, supra, at 99–101, 481 N. E. 2d, at 694–695).

We have generally given considerable weight to the find-
ings of state and lower federal courts regarding the intent
or purpose underlying state officials’ actions, see U. S. Term
Limits, Inc. v. Thornton, 514 U. S. 779, 829 (1995) (ordinarily
“[w]e must . . . accept the state court’s view of the purpose
of its own law”); Romer v. Evans, 517 U. S. 620, 626 (1996);
Hernandez v. New York, 500 U. S. 352, 366–370 (1991) (plu-
rality opinion); id., at 372 (O’Connor, J., concurring); Ed-
wards v. Aguillard, 482 U. S. 578, 594, n. 15 (1987); but see
Department of Revenue of Mont. v. Kurth Ranch, 511 U. S.,
at 776, 780, n. 18; Stone v. Graham, 449 U. S. 39, 40–43 (1980)
(per curiam); Consolidated Edison Co. of N. Y. v. Public
Serv. Comm’n of N. Y., 447 U. S. 530, 533, 535–537 (1980),
although the level of deference given to such findings varies
with the circumstances, Crawford v. Board of Ed. of Los
Angeles, 458 U. S. 527, 544, n. 30 (1982), and is not always as
conclusive as a state court’s construction of one of its stat-

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384 KANSAS v. HENDRICKS

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utes, see, e. g., R. A. V. v. St. Paul, 505 U. S. 377, 381 (1992).
For example, Allen’s dissenters, as well as its majority, con-
sidered the state court’s characterization of the state law’s
purpose an important factor in determining the constitution-
ality of that statute. Allen, 478 U. S., at 380 (Stevens, J.,
dissenting) (describing the state court as “the final authority
on the . . . purpose” of the statute).

The record provides support for the Kansas court’s con-
clusion. The court found that, as of the time of Hendricks’
commitment, the State had not funded treatment, it had not
entered into treatment contracts, and it had little, if any,
qualified treatment staff. See 259 Kan., at 249, 258, 912
P. 2d, at 131, 136; Testimony of Dr. Charles Befort, App. 255
(acknowledging that he has no specialized training); Testi-
mony of John House, SRS Attorney, id., at 367 (no contract
has been signed by bidders); Testimony of John House, SRS
Attorney, id., at 369 (no one hired to operate sexually vio-
lent predator (SVP) program or to serve as clinical director,
psychiatrist, or psychologist). Indeed, were we to follow
the majority’s invitation to look beyond the record in this
case, an invitation with which we disagree, see infra, at
391–393, it would reveal that Hendricks, according to the
commitment program’s own director, was receiving “essen-
tially no treatment.” Dr. Charles Befort in State Habeas
Corpus Proceeding, App. 393; 259 Kan., at 249, 258, 912 P. 2d,
at 131, 136. See also App. 421 (“[T]he treatment that is pre-
scribed by statute” is “still not available”); id., at 420–421
(the “needed treatment” “hasn’t been delivered yet” and
“Hendricks has wasted ten months” in “terms of treatment
effects”); id., at 391–392 (Dr. Befort admitting that he is not
qualified to be SVP program director).

It is therefore not surprising that some of the Act’s official
supporters had seen in it an opportunity permanently to con-
fine dangerous sex offenders, e. g., id., at 468 (statement of
Attorney General Robert Stephan); id., at 475–476, 478
(statement of Special Assistant to the Attorney General

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Breyer, J., dissenting

Carla Stovall). Others thought that effective treatment did
not exist, id., at 503 (statement of Jim Blaufuss) (“Because
there is no effective treatment for sex offenders, this Bill
may mean a life sentence for a felon that is considered a risk
to women and children. SO BE IT!”)—a view, by the way,
that the State of Kansas, supported by groups of informed
mental health professionals, here strongly denies. See
supra, at 378.

The Kansas court acknowledged the existence of “provi-
sions of the Act for treatment” (although it called them
“somewhat disingenuous”). 259 Kan., at 258, 912 P. 2d, at
136. Cf. Kan. Stat. Ann. § 59–29a01 (1994) (legislative find-
ings that “prognosis for rehabilita[tion] . . . in a prison setting
is poor, . . . treatment needs . . . long term” and “commitment
procedure for . . . long term care and treatment . . . neces-
sary”); § 59–29a09 (“commitment . . . shall conform to consti-
tutional requirements for care and treatment”). Nor did the
court deny that Kansas could later increase the amount of
treatment it provided. But the Kansas Supreme Court
could, and did, use the Act’s language, history, and initial
implementation to help it characterize the Act’s primary
purposes.

Second, the Kansas statute, insofar as it applies to pre-
viously convicted offenders such as Hendricks, commits,
confines, and treats those offenders after they have served
virtually their entire criminal sentence. That time-related
circumstance seems deliberate. The Act explicitly defers
diagnosis, evaluation, and commitment proceedings until a
few weeks prior to the “anticipated release” of a previously
convicted offender from prison. Kan. Stat. Ann. § 59–
29a03(a)(1) (1994). But why, one might ask, does the Act not
commit and require treatment of sex offenders sooner, say,
soon after they begin to serve their sentences?

An Act that simply seeks confinement, of course, would
not need to begin civil commitment proceedings sooner.
Such an Act would have to begin proceedings only when an

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offender’s prison term ends, threatening his release from the
confinement that imprisonment assures. But it is difficult
to see why rational legislators who seek treatment would
write the Act in this way—providing treatment years after
the criminal act that indicated its necessity. See, e. g., Wett-
stein, A Psychiatric Perspective on Washington’s Sexually
Violent Predators Statute, 15 U. Puget Sound L. Rev. 597,
617 (1992) (stating that treatment delay leads to “loss of
memory” and makes it “more difficult for the offender” to
“accept responsibility,” and that time in prison leads to at-
titude hardening that “engender[s] a distorted view of the
precipitating offense”). And it is particularly difficult to see
why legislators who specifically wrote into the statute a
finding that “prognosis for rehabilitating . . . in a prison set-
ting is poor” would leave an offender in that setting for
months or years before beginning treatment. This is to
say, the timing provisions of the statute confirm the Kansas
Supreme Court’s view that treatment was not a particularly
important legislative objective.

I recognize one possible counterargument. A State,
wanting both to punish Hendricks (say, for deterrence pur-
poses) and also to treat him, might argue that it should be
permitted to postpone treatment until after punishment in
order to make certain that the punishment in fact occurs.
But any such reasoning is out of place here. Much of the
treatment that Kansas offered here (called “ward milieu” and
“group therapy”) can be given at the same time as, and in
the same place where, Hendricks serves his punishment.
See, e. g., Testimony of Leroy Hendricks, App. 142–143, 150,
154, 179–181 (stating that Washington and Kansas had both
provided group therapy to Hendricks, and that he had both
taken and refused such treatment at various points); Testi-
mony of Terry Davis, SRS Director of Quality Assurance,
id., at 78–81 (pointing out that treatment under the Act
takes place in surroundings very similar to those in which
prisoners receive treatment); Testimony of John House, SRS

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Breyer, J., dissenting

Attorney, id., at 375–376. See also Task Force on Commu-
nity Protection, Final Report to Booth Gardner, Governor
State of Washington II–2 (1989) (findings of task force that
developed the Washington State Act, which served as a
model for Kansas’ Act, stating that “[s]ex offenders can be
treated during incarceration”). The evidence adduced at
the state habeas proceeding, were we to assume it properly
before the Court, see infra, at 392–393, supports this conclu-
sion as well. See Testimony of Dr. Befort at State Habeas
Proceeding, App. 399, 406–408 (describing treatment as ward
milieu and group therapy); id., at 416–417 (stating that Kan-
sas offers similar treatment, on a voluntary basis, to prison-
ers). Hence, assuming, arguendo, that it would be other-
wise permissible, Kansas need not postpone treatment in
order to make certain that sex offenders serve their full
terms of imprisonment, i. e., to make certain that they re-
ceive the entire punishment that Kansas criminal law pro-
vides. To the contrary, the statement in the Act itself, that
the Act aims to respond to special “long term” “treatment
needs,” suggests that treatment should begin during impris-
onment. It also suggests that, were those long-term treat-
ment needs (rather than further punishment) Kansas’ pri-
mary aim, the State would require that treatment begin soon
after conviction, not 10 or more years later. See also Vt.
Stat. Ann., Tit. 18, § 2815 (1959) (providing for treatment of
sexual psychopaths first, and punishment afterwards).

Third, the statute, at least as of the time Kansas applied
it to Hendricks, did not require the committing authority to
consider the possibility of using less restrictive alternatives,
such as postrelease supervision, halfway houses, or other
methods that amici supporting Kansas here have mentioned.
Brief for Menninger Foundation et al. as Amici Curiae 28;
Brief for Association for the Treatment of Sexual Abusers
as Amicus Curiae 11–12. The laws of many other States
require such consideration. See Appendix, infra.

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388 KANSAS v. HENDRICKS

Breyer, J., dissenting

This Court has said that a failure to consider, or to use,
“alternative and less harsh methods” to achieve a nonpuni-
tive objective can help to show that legislature’s “purpose
. . . was to punish.” Bell v. Wolfish, 441 U. S. 520, 539, n. 20
(1979). And one can draw a similar conclusion here. Legis-
lation that seeks to help the individual offender as well as to
protect the public would avoid significantly greater restric-
tion of an individual’s liberty than public safety requires.
See Keilitz, Conn, & Gianpetro, Least Restrictive Treatment
of Involuntary Patients: Translating Concepts into Practice,
29 St. Louis U. L. J. 691, 693 (1985) (describing “least restric-
tive alternativ[e]” provisions in the ordinary civil commit-
ment laws of almost all States); Lyon, Levine, & Zusman,
Patients’ Bill of Rights: A Survey of State Statutes, 6 Mental
Disability L. Rep. 178, 181–183 (1982) (same). Legislation
that seeks almost exclusively to incapacitate the individual
through confinement, however, would not necessarily con-
cern itself with potentially less restrictive forms of incapaci-
tation. I would reemphasize that this is not a case in which
the State claims there is no treatment potentially available.
Rather, Kansas, and supporting amici, argue that pedophilia
is treatable. See supra, at 378.

Fourth, the laws of other States confirm, through compari-
son, that Kansas’ “civil commitment” objectives do not re-
quire the statutory features that indicate a punitive purpose.
I have found 17 States with laws that seek to protect the
public from mentally abnormal, sexually dangerous individu-
als through civil commitment or other mandatory treatment
programs. Ten of those statutes, unlike the Kansas statute,
begin treatment of an offender soon after he has been appre-
hended and charged with a serious sex offense. Only seven,
like Kansas, delay “civil” commitment (and treatment) until
the offender has served his criminal sentence (and this figure
includes the Acts of Minnesota and New Jersey, both of
which generally do not delay treatment). Of these seven,
however, six (unlike Kansas) require consideration of less re-

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389Cite as: 521 U. S. 346 (1997)

Breyer, J., dissenting

strictive alternatives. See Ariz. Rev. Stat. Ann. §§ 13–4601,
4606B (Supp. 1996–1997); Cal. Welf. & Inst. Code Ann.
§§ 6607, 6608 (West Supp. 1997); Minn. Stat. § 253B.09 (1996);
N. J. Stat. Ann. § 30:4–27.11d (West 1997); Wash. Rev. Code
Ann. § 71.09.090 (Supp. 1996–1997); Wis. Stat. § 980.06(2)(b)
(Supp. 1993–1994). Only one State other than Kansas,
namely Iowa, both delays civil commitment (and consequent
treatment) and does not explicitly consider less restrictive
alternatives. But the law of that State applies prospec-
tively only, thereby avoiding ex post facto problems. See
Iowa Code Ann. § 709C.12 (Supp. 1997) (Iowa SVP Act only
“applies to persons convicted of a sexually violent offense on
or after July 1, 1997”); see also Appendix, infra. Thus the
practical experience of other States, as revealed by their
statutes, confirms what the Kansas Supreme Court’s finding,
the timing of the civil commitment proceeding, and the fail-
ure to consider less restrictive alternatives, themselves sug-
gest, namely, that for Ex Post Facto Clause purposes, the
purpose of the Kansas Act (as applied to previously convicted
offenders) has a punitive, rather than a purely civil, purpose.

Kansas points to several cases as support for a contrary
conclusion. It points to Allen—which is, as we have seen, a
case in which the Court concluded that Illinois’ “civil commit-
ment” proceedings were not criminal. I have explained in
detail, however, how the statute here differs from that in
Allen, and why Allen’s reasoning leads to a different conclu-
sion in this litigation. See supra, at 381–388 and this page.

Kansas also points to Addington v. Texas, where the Court
held that the Constitution does not require application of
criminal law’s “beyond a reasonable doubt” standard in a
civil commitment proceeding. 441 U. S., at 428. If some
criminal law guarantees such as “reasonable doubt” did not
apply in Addington, should other guarantees, such as the
prohibition against ex post facto laws, apply here? The an-
swer to this question, of course, lies in the particular statute
at issue in Addington—a Texas statute that, this Court ob-

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390 KANSAS v. HENDRICKS

Breyer, J., dissenting

served, did “not exercis[e]” state power “in a punitive sense.”
Ibid. That statute did not add civil commitment’s confine-
ment to imprisonment; rather civil commitment was, at most,
a substitute for criminal punishment. See Tex. Rev. Civ.
Stat. Ann. § 5547–41 (Vernon 1958) (petition must state “pro-
posed patient is not charged with a crime or [is] charged
[but] transferred . . . for civil commitment proceedings”).
And this Court, relying on the Texas Supreme Court’s inter-
pretation, wrote that the “State of Texas confines only for
the purpose of providing care designed to treat the individ-
ual.” Addington, supra, at 428, n. 4 (citing State v. Turner,
556 S. W. 2d 563, 566 (1977)). Cf. Specht v. Patterson, 386
U. S. 605, 608–609 (1967) (separate postconviction sexual psy-
chopath commitment/sentencing proceeding held after con-
viction for serious sex crime, imposes a “criminal punish-
ment even though . . . designed not so much as retribution
as . . . to keep individuals from inflicting future harm”).
Nothing I say here would change the reach or holding of
Addington in any way. That is, a State is free to commit
those who are dangerous and mentally ill in order to treat
them. Nor does my decision preclude a State from deciding
that a certain subset of people are mentally ill, dangerous,
and untreatable, and that confinement of this subset is there-
fore necessary (again, assuming that all the procedural safe-
guards of Addington are in place). But when a State de-
cides offenders can be treated and confines an offender to
provide that treatment, but then refuses to provide it, the
refusal to treat while a person is fully incapacitated begins
to look punitive.

The majority suggests that this is the very case I say it is
not, namely, a case of a mentally ill person who is untreat-
able. Ante, at 365. And it quotes a long excerpt from the
Kansas Supreme Court’s opinion in support. That court,
however, did not find that Hendricks was untreatable; it
found that he was untreated—quite a different matter. Had
the Kansas Supreme Court thought that Hendricks, or oth-

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391Cite as: 521 U. S. 346 (1997)

Breyer, J., dissenting

ers like him, are untreatable, it could not have written the
words that follow that excerpt, adopting by reference the
words of another court opinion:

“ ‘The statute forecloses the possibility that offenders
will be evaluated and treated until after they have been
punished. . . . Setting aside the question of whether a
prison term exacerbates or minimizes the mental con-
dition of a sex offender, it plainly delays the treatment
that must constitutionally accompany commitment pur-
suant to the Statute. The failure of the Statute to pro-
vide for examination or treatment prior to the com-
pletion of the punishment phase strongly suggests that
treatment is of secondary, rather than primary, con-
cern.’ ” 259 Kan., at 258, 912 P. 2d, at 136 (quoting Young
v. Weston, 898 F. Supp. 744, 753 (WD Wash. 1995)).

This quotation, and the rest of the opinion, make clear that
the court is finding it objectionable that the statute, among
other things, has not provided adequate treatment to one
who, all parties here concede, can be treated.

The majority suggests in the alternative that recent evi-
dence shows that Kansas is now providing treatment. Ante,
at 366–368. That evidence comes from two sources: First, a
statement by the Kansas Attorney General at oral argument
that those committed under the Act are now receiving treat-
ment, ante, at 368; and second, in a footnote, a Kansas trial
judge’s statement, in a state habeas proceeding nearly one
year after Hendricks was committed, that Kansas is provid-
ing treatment. Ante, at 368, n. 5. I do not see how either
of these statements can be used to justify the validity of the
Act’s application to Hendricks at the time he filed suit.

We are reviewing the Kansas Supreme Court’s determi-
nation of Hendricks’ case. Neither the majority nor the
lengthy dissent in that court referred to the two facts that
the majority now seizes upon, and for good reason. That
court denied a motion to take judicial notice of the state

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392 KANSAS v. HENDRICKS

Breyer, J., dissenting

habeas proceeding, see Order of Kansas Supreme Court,
No. 94–73039, Mar. 1, 1996. The proceeding is thus not part
of the record, and cannot properly be considered by this
Court. And the Kansas Supreme Court obviously had no
chance to consider Kansas’ new claim made at oral argument
before this Court. There is simply no evidence in the record
before this Court that comes even close to resembling the
assertion Kansas made at oral argument. It is the record,
not the parties’ view of it, that must control our decision.
See Russell v. Southard, 12 How. 139, 158–159 (1851); Ad-
ickes v. S. H. Kress & Co., 398 U. S. 144, 157–158, n. 16 (1970);
Hopt v. Utah, 114 U. S. 488, 491–492 (1885); Witters v. Wash-
ington Dept. of Servs. for Blind, 474 U. S. 481, 489, n. 3
(1986); New Haven Inclusion Cases, 399 U. S. 392, 450, n. 66
(1970); R. Stern, E. Gressman, S. Shapiro, & K. Geller, Su-
preme Court Practice 555–556, 594 (7th ed. 1993); Fed. Rule
Evid. 201(b).

The prohibition on facts found outside the record is de-
signed to ensure the reliability of the evidence before the
Court. For purposes of my argument in this dissent, how-
ever, the material that the majority wishes to consider, when
read in its entirety, shows that Kansas was not providing
treatment to Hendricks. At best, the testimony at the state
hearing contained general and vague references that treat-
ment was about to be provided, but it contains no statement
that Hendricks himself was receiving treatment. And it
provides the majority with no support at all in respect to
that key fact. Indeed, it demonstrates the contrary conclu-
sion. For example, the program’s director, Dr. Befort, testi-
fied that he would have to tell the court at Hendricks’ next
annual review, in October 1995, that Hendricks “has had no
opportunity for meaningful treatment.” App. 400. He also
stated that SVP’s were receiving “essentially no treatment”
and that the program does not “have adequate staffing.”
Id., at 393, 394. And Dr. Befort’s last words made clear that
Hendricks has “wasted ten months . . . in terms of treatment

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Breyer, J., dissenting

effects” and that, as far as treatment goes, “[t]oday, it’s still
not available.” Id., at 420–421. Nor does the assertion
made by the Kansas Attorney General at oral argument help
the majority. She never stated that Hendricks, as opposed
to other SVP’s, was receiving this treatment. And we can
find no support for her statement in the record.

We have found no other evidence in the record to support
the conclusion that Kansas was in fact providing the treat-
ment that all parties agree that it could provide. Thus, even
had the Kansas Supreme Court considered the majority’s
new evidence—which it did not—it is not likely to have
changed its characterization of the Act’s treatment provi-
sions as “somewhat disingenuous.” 259 Kan., at 258, 912
P. 2d, at 136.

Regardless, the Kansas Supreme Court did so characterize
the Act’s treatment provisions and did find that treatment
was “at best” an “incidental” objective. Thus, the circum-
stances here are different from Allen, where the Illinois Su-
preme Court explicitly found that the statute’s aim was to
provide treatment, not punishment. See supra, at 382–384.
There is no evidence in the record that contradicts the find-
ing of the Kansas court. Thus, Allen’s approach—its reli-
ance on the state court—if followed here would mean the Act
as applied to Leroy Hendricks (as opposed to others who
may have received treatment or who were sentenced after
the effective date of the Act) is punitive.

Finally, Kansas points to United States v. Salerno, 481
U. S. 739 (1987), a case in which this Court held preventive
detention of a dangerous accused person pending trial consti-
tutionally permissible. Salerno, however, involved the brief
detention of that person, after a finding of “probable cause”
that he had committed a crime that would justify further
imprisonment, and only pending a speedy judicial determina-
tion of guilt or innocence. This Court, in Foucha, empha-
sized the fact that the confinement at issue in Salerno was
“strictly limited in duration.” 504 U. S., at 82. It described

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394 KANSAS v. HENDRICKS

Breyer, J., dissenting

that “pretrial detention of arrestees” as “one of those care-
fully limited exceptions permitted by the Due Process
Clause.” Id., at 83. And it held that Salerno did not au-
thorize the indefinite detention, on grounds of dangerous-
ness, of “insanity acquittees who are not mentally ill but who
do not prove they would not be dangerous to others.” 504
U. S., at 83. Whatever Salerno’s “due process” implications
may be, it does not focus upon, nor control, the question at
issue here, the question of “punishment” for purposes of the
Ex Post Facto Clause.

One other case warrants menti on. In Kennedy v.
Mendoza-Martinez, 372 U. S. 144 (1963), this Court listed
seven factors that helped it determine whether a particular
statute was primarily punitive for purposes of applying the
Fifth and Sixth Amendments. Those factors include
whether a sanction involves an affirmative restraint, how
history has regarded it, whether it applies to behavior al-
ready a crime, the need for a finding of scienter, its relation-
ship to a traditional aim of punishment, the presence of a
nonpunitive alternative purpose, and whether it is excessive
in relation to that purpose. Id., at 169. This Court has said
that these seven factors are “neither exhaustive nor disposi-
tive,” but nonetheless “helpful.” Ward, 448 U. S., at 249.
Paraphrasing them here, I believe the Act before us involves
an affirmative restraint historically regarded as punishment;
imposed upon behavior already a crime after a finding of
scienter; which restraint, namely, confinement, serves a tra-
ditional aim of punishment, does not primarily serve an al-
ternative purpose (such as treatment), and is excessive in
relation to any alternative purpose assigned. 372 U. S., at
168–169.

This is not to say that each of the factors the Court men-
tioned in Martinez-Mendoza on balance argues here in favor
of a constitutional characterization as “punishment.” It is
not to say that I have found “a single ‘formula’ for identify-
ing those legislative changes that have a sufficient effect on

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Breyer, J., dissenting

substantive crimes or punishments to fall within the con-
stitutional prohibition,” Morales, 514 U. S., at 509; see also
Halper, 490 U. S., at 447; id., at 453 (Kennedy, J., con-
curring). We have not previously done so, and I do not do
so here. Rather, I have pointed to those features of the
Act itself, in the context of this litigation, that lead me to
conclude, in light of our precedent, that the added confine-
ment the Act imposes upon Hendricks is basically punitive.
This analysis, rooted in the facts surrounding Kansas’ fail-
ure to treat Hendricks, cannot answer the question whether
the Kansas Act, as it now stands, and in light of its current
implementation, is punitive toward people other than he.
And I do not attempt to do so here.

III

To find that the confinement the Act imposes upon Hen-
dricks is “punishment” is to find a violation of the Ex Post
Facto Clause. Kansas does not deny that the 1994 Act
changed the legal consequences that attached to Hendricks’
earlier crimes, and in a way that significantly “disadvan-
tage[d] the offender,” Weaver v. Graham, 450 U. S. 24, 29
(1981). See Brief for Respondent State of Kansas 37–39.

To find a violation of that Clause here, however, is not to
hold that the Clause prevents Kansas, or other States, from
enacting dangerous sexual offender statutes. A statute that
operates prospectively, for example, does not offend the Ex
Post Facto Clause. Weaver, 450 U. S., at 29. Neither does
it offend the Ex Post Facto Clause for a State to sentence
offenders to the fully authorized sentence, to seek con-
secutive, rather than concurrent, sentences, or to invoke
recidivism statutes to lengthen imprisonment. Moreover, a
statute that operates retroactively, like Kansas’ statute,
nonetheless does not offend the Clause if the confinement
that it imposes is not punishment—if, that is to say, the
legislature does not simply add a later criminal punishment
to an earlier one. Ibid.

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396 KANSAS v. HENDRICKS

Breyer, J., dissenting

The statutory provisions before us do amount to punish-
ment primarily because, as I have said, the legislature did
not tailor the statute to fit the nonpunitive civil aim of treat-
ment, which it concedes exists in Hendricks’ case. The
Clause in these circumstances does not stand as an obstacle
to achieving important protections for the public’s safety;
rather it provides an assurance that, where so significant a
restriction of an individual’s basic freedoms is at issue, a
State cannot cut corners. Rather, the legislature must hew
to the Constitution’s liberty-protecting line. See The Fed-
eralist No. 78, p. 466 (C. Rossiter ed. 1961) (A. Hamilton).

I therefore would affirm the judgment below.

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Appendix to opinion of Breyer, J.

APPENDIX TO OPINION OF BREYER, J.

Selected Sexual Offense Commitment Statutes
(Kansas is the only State that answers “yes”

to all three categories)

Fails to
Consider Less Applies to

Delays Restrictive Pre-Act
State Treatment Alternatives Crimes

Ariz. Rev. Stat. Ann.
§ 13–4601 et seq.
(Supp. 1996–1997) Yes No *

Cal. Welf. & Inst. Code
Ann. § 6600 et seq.
(West Supp. 1997) Yes No Yes

Colo. Rev. Stat.
§ 16–11.7–101 et seq. Some-
(Supp. 1996) No Yes times

Conn. Gen. Stat.
§ 17a–566 et seq. (1992
and Supp. 1996) No * *

Ill. Comp. Stat.,
ch. 725, § 205 et seq.
(1994) No No

Iowa Code Ann.
ch. 709C (Supp. 1996) Yes Yes No

Kan. Stat. Ann. § 59–
29a01 et seq. (1994) Yes Yes Yes

Mass. Gen. Laws,
ch. 123A (Supp. 1997) No * *

Minn. Stat. Ann.,
ch. 253B (1994 and Some-
Supp. 1996–1997) times No Yes

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398 KANSAS v. HENDRICKS

Appendix to opinion of Breyer, J.

Selected Sexual Offense Commitment
Statutes—Continued

Fails to
Consider Less Applies to
Delays Restrictive Pre-Act
State Treatment Alternatives Crimes

Neb. Rev. Stat.
§ 29–2923 et seq. Generally
(Supp. 1996) No No not

N. J. Stat. Ann.
§ 30:4–82.4 et seq. Some-
(West 1997) times No *

N. M. Stat. Ann.
§ 43–1–1 et seq. (1993) No No *

Ore. Rev. Stat. Generally
§ 426.510 et seq. (1995) No Yes not

Tenn. Code Ann.
§ 33–6–301 et seq. (1984
and Supp. 1996) No Yes *

Utah Code Ann. Generally
§ 77–16–1 et seq. (1995) No Yes not

Wash. Rev. Code Ann.
§ 71.09.01 et seq. (1992
and Supp. 1996–1997) Yes No Yes

Wis. Stat. § 980.010
et seq. (Supp.
1993–1994) Yes No Yes

(* = designation that the statute does not specify)