Each state, as well as the District of Columbia, has its own law describing the standard for determining whether a defendant is legally insane, and therefore not responsible, at the time the crime is committed . “A madness defense is based on the theory that most people can choose to follow the law; but a select few people cannot be held responsible because mental illness or disability deprives them of the ability to make a rational/voluntary choice. These people need special treatment rather than prison; punishment is unlikely to deter future antisocial behavior from these mentally ill people. Retrieved 05/25/2010 from http://www.law.umkc.edu/faculty/projects/ftrials/hinckley/EVOL.HTMIThere are essentially two categories, the M'Naghten rule and the American Law Institute model . States are roughly divided between these two categories, with the exception of Montana, Idaho, and Utah which do not allow the insanity defense. The M'Naghten rule provides as follows: "Every man must be presumed to be of sound mind, and ... that in order to establish a defense of insanity it must be clearly proven that at the time of the commission of the act, the accused party suffered from such defect of reason, mental illness, and not knowing the nature and quality of the act he was committing; or if he did, he didn't know he was doing the wrong thing. » Retrieved 05/21/10 from http://criminal.findlaw. com/crimes/more-criminal-topics/insanity-defense/the-mnaghten-rule.htmlThe test used under the M'Naghten standard, commonly referred to as the "good/bad" test, to determine whether a defendant can distinguish the law of evil is based on the idea that the defendant must know the difference of each...... middle of paper ......a.Works CitedKnowles, Brian (2000). Does the insanity plea allow criminals to escape justice? Accessed 05/25/2010 from http://www.speakout.com/activism/issue_briefs/1229b-1.htmlMontaldo, Charles (nd) The Insanity Defense; The standard for legal insanity has changed. Retrieved 05/19/2010 from http://crime.about.com/od/issues/a/insanity.htmThe "M'Naghten Rule" (nd) Retrieved 05/21/10 from http://criminal. findlaw.com/crimes/more-criminal-topics/insanity-defense/the-mnaghten-rule.htmlhttp://www.lectlaw.com/def/d029.htmhttp://www.justice.gov/usao/eousa/ foia_reading_room/usam/title9/crm00634.htmhttp://www.enotes.com/everyday-law-encyclopedia/insanity-defense#american-law-institutes-model-penal-code-testEvolution of Insanity Advocacy (nd). Accessed 05/25/2010 from http://www.law.umkc.edu/faculty/projects/ftrials/hinckley/EVOL.HTM