People with mental illness are subject to special treatment in all three settings in which the law deprives people of liberty. In criminal cases, only people with mental illness have a special defense (insanity). In the preventive detention setting, only people with mental disorders can be subject to long-term police power commitment based on a prediction that they are dangerous to others. In most jurisdictions, only people with mental illness are presumed incompetent and thus subject to involuntary hospitalization or guardianship under the state’s parens patriae power. The impact of insanity defense on civil liberties is discussed in that entry.
Police power commitment at one time was reserved for people whose impairment was so serious they would be considered insane were they to commit a crime. But in Kansas v. Hendricks, 521 U.S. 346 (1997), the U.S. Supreme Court held that even sane individuals, such as sex offenders, may be subject to prolonged detention based on a prediction of danger, as long as they have a ‘‘mental abnormality’’ that makes them ‘‘dangerous beyond their control.’’ With respect to the state’s parens patriae authority, the Court held in O’Connor v. Donaldson, 422 U.S. 563 (1976), that the state may not commit someone merely because he or she is mentally ill or if he or she can survive safely in freedom with the help of relatives or friends. Nonetheless, in many jurisdictions, homeless people who would rather be on the streets can be hospitalized, and people who are committed can be forcibly medicated even if they give plausible reasons for not wanting the medication.
References and Further Reading
Cases and Statutes Cited
See also Dusky v. U.S., 362 U.S. 402 (1961); Guilty but Mentally Ill; Insanity Defense; Jackson v. Indiana, 406 U.S. 715 (1972); Riggins v. Nevada, 504 U.S. 127 (1992)