Also known as: dangerous lunatics · insane person · mentally disordered offender
Written by attorneys · grounded in primary & secondary sources — see below
A mentally incompetent person who seems reasonably likely to harm himself or herself, another person, or property.
Denise Donovan, a dangerous lunatic, wandered onto a construction site and ignored visible barriers. When she fell and sued the site owner, the owner raised contributory negligence. Because she qualified as an insane person under the governing rule, the jury measured her conduct by a standard other than that of a reasonable adult.
Darrell Duncan, a dangerous lunatic on death row, displayed no understanding of his impending execution. The state sought to proceed with the sentence. The court halted the execution because the prisoner's mental condition barred carrying out the penalty.
Select any source to read its text and confirm it supports the definition.
Demetrius Douglas, found not guilty by reason of insanity after an assault, remained a dangerous lunatic. Louisiana sought to keep him institutionalized. The court permitted ongoing confinement because his dangerous condition justified detention beyond the criminal sentence.
Doris Duffy raised an insanity defense after a homicide. Oregon required her to prove beyond a reasonable doubt that she was a dangerous lunatic at the time of the act. The Supreme Court upheld the burden allocation as consistent with due process.
Daniel Diaz, a dangerous lunatic facing execution, held delusional beliefs that severed his understanding of the state's reasons for the sentence. The court stayed the execution because the prisoner's mental state prevented comprehension of the penalty's basis.
Diane Dawson, previously adjudged a dangerous lunatic, challenged her loss of voting rights after a felony conviction. The state defended the permanent disenfranchisement. The Court upheld the restriction as within the state's authority over felons.
A dangerous lunatic falls outside the ordinary reasonable-person standard for contributory negligence. The governing rule applies the adult objective standard only when the actor is neither a child nor an insane person. Therefore a plaintiff who meets the dangerous-lunatic definition receives a different, more protective measure of self-protective conduct.
Supporting sources
Yes. A state may keep a dangerous lunatic institutionalized after an insanity acquittal so long as the person remains dangerous. The confinement rests on the ongoing mental condition rather than on punishment for the original offense.
Supporting sources
No. The Eighth Amendment forbids execution of a prisoner who is insane at the time of execution. A dangerous lunatic who lacks awareness of the punishment and its reasons cannot be put to death.
Supporting sources
…the commission of murder, namely, culpability for his muscular contraction. Like every other State, Oregon presupposes that an insane person cannot be made to pay with his life for a homicide, though for the public good he may of course be put beyond doing further harm. Unlike every other State, however, Oregon says that the…