The U.S. Supreme Court is looking anew at the insanity defense, a centuries-old legal doctrine, which holds that some mentally ill defendants do not know right from wrong and cannot be held responsible for their crimes. Supporters of the insanity defense say such individuals need psychiatric treatment, not imprisonment. But critics say the insanity defense is often a “get-out-of-jail” card that enables criminals to avoid punishment. The issue at stake in the Supreme Court case is whether a state that abolishes the insanity defense is violating the U.S. Constitution. A Kansas man facing the death penalty in a quadruple homicide says a state law abolishing the insanity defense unconstitutionally prevented him from arguing that his actions were the result of his mental illness. Many legal experts say the Kansas law — and similar ones in three other states — violate legal precedents and moral norms. But other experts and crime victims' groups say the Constitution allows states to establish their own criminal laws.