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National Crime Victim Law Institute

What if a defendant has mental health problems and/or raises the insanity defense?

December 10, 2012

When a person charged with a crime has mental health concerns several things can occur.  Two are highlighted here.  First, the defendant may plead not guilty by reason of insanity.  In most states, the defendant must prove insanity by a preponderance of the evidence.  In some states, the prosecution must prove the defendant is or was sane beyond a reasonable doubt.   In federal court, defendant must prove insanity by clear and convincing evidence.  Defendants who are found not guilty by reason of insanity are generally required to undergo psychiatric treatment and are placed in a mental health facility.  Unlike defendants who are found guilty, they are not institutionalized for a fixed period, but rather they are held until they are determined to no longer be a threat to the community or themselves.   The Psychiatric Security Review Board (PSRB), or a similar body in most jurisdictions, regularly reviews the defendant’s treatment progress and hold hearings on whether the defendant should be released. 


Second, in some jurisdictions there may be Guilty but Mentally Ill or a Guilty but Insane verdicts.   Persons who receive these verdicts face prison sentences of the same length as a guilty verdict and often have other requirements put on them such as incarceration to the prison’s psychiatric ward and mandatory treatment during parole.