## Facts

- Kansas enacted the Sexually Violent Predator Act authorizing civil commitment of persons likely to commit predatory sexual violence due to a “mental abnormality” or “personality disorder.”
- The Act defined “mental abnormality” as a congenital or acquired condition affecting emotional or volitional capacity that predisposes a person to commit sexually violent offenses to the degree the person is a menace to others.
- Leroy Hendricks, nearing completion of a prison sentence, had a long history of molesting children.
- Kansas sought Hendricks’s civil commitment under the Act as his release approached.
- At trial, Hendricks acknowledged a diagnosis of pedophilia, stated he was not cured, and reported persistent sexual desires for children he could not control when stressed.
- A jury found Hendricks to be a sexually violent predator, and the court ordered his civil commitment, concluding pedophilia qualified as a “mental abnormality” under the Act.
- The Kansas Supreme Court held the Act unconstitutional on substantive due process grounds, reasoning involuntary commitment required “mental illness,” and did not reach double jeopardy or ex post facto claims.
- The U.S. Supreme Court granted review.

## Issues

1. Whether substantive due process permits involuntary civil commitment based on a statutory “mental abnormality” standard rather than a “mental illness” label when coupled to dangerousness.
2. Whether commitment under the Act constitutes punishment, thereby violating the Double Jeopardy Clause or Ex Post Facto Clause when applied to persons already convicted and imprisoned.

## Decision

- The Supreme Court reversed and upheld the Act.
- Substantive due process was satisfied because the Act requires a finding of dangerousness linked to a qualifying mental condition that limits commitment to persons with impaired emotional or volitional capacity who are likely to commit sexual violence.
- The Constitution does not require a particular medical term (such as “mental illness”) if the statutory criteria functionally identify a disorder connected to inability to control dangerous behavior.
- The Act was deemed civil, not criminal, in legislative intent and operation.
- Because the Act is civil and nonpunitive, it did not impose a second punishment (no double jeopardy) and did not impose retroactive punishment (no ex post facto violation).

## Legal Principles

- Civil commitment may comport with due process when it requires (1) proof of dangerousness and (2) proof of an additional limiting condition (such as mental abnormality or personality disorder) that meaningfully narrows confinement to those whose impairment contributes to dangerousness.
- Due process does not mandate use of the term “mental illness”; functional criteria tied to impaired emotional or volitional capacity and likelihood of sexually violent conduct can suffice.
- A statutory commitment scheme is not “punishment” for double jeopardy or ex post facto purposes when the legislature establishes a civil proceeding and the scheme’s design and effects are oriented to treatment and incapacitation based on current condition and dangerousness.
- Indefinite commitment is permissible in the civil context if continued confinement depends on ongoing satisfaction of statutory criteria and release is required when the person is no longer dangerous under the Act’s standards.

## Conclusion

The Court held that Kansas may civilly commit sexually violent predators based on a defined mental abnormality linked to dangerousness without using a “mental illness” label, and that the resulting confinement is not criminal punishment triggering double jeopardy or ex post facto limits when the scheme is civil in intent and effect.


Kansas v. Hendricks, 521 U.S. 346 (1997)