{"id":352322,"date":"2023-12-09T13:49:39","date_gmt":"2023-12-09T18:49:39","guid":{"rendered":"https:\/\/content.findlaw-admin.com\/ability-law\/criminal\/criminal-procedure\/the-insanity-defense-history-and-background.html"},"modified":"2023-12-09T13:49:39","modified_gmt":"2023-12-09T18:49:39","slug":"the-insanity-defense-history-and-background","status":"publish","type":"page","link":"https:\/\/www.findlaw.com\/criminal\/criminal-procedure\/the-insanity-defense-history-and-background.html","title":{"rendered":"Background and History of the Insanity Defense"},"content":{"rendered":"\n
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Background and History of the Insanity Defense<\/h1>\n
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\n By Samuel Strom, J.D.<\/a> | Legally reviewed by Melissa Bender, Esq.<\/a>\n | Last updated\n
\n \n <\/i>\n Legally Reviewed\n <\/summary>\n\n
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This article has been written and reviewed for legal accuracy, clarity, and style by FindLaw\u2019s team of legal writers and attorneys<\/a> and in accordance with our editorial standards<\/a>.<\/em><\/p>\n\n <\/div>\n <\/details>\n\n

\n \n <\/i>\n Fact-Checked\n <\/summary>\n\n
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The last updated date refers to the last time this article was reviewed by FindLaw or one of our contributing authors<\/a>. We make every effort to keep our articles updated. For information regarding a specific legal issue affecting you, please contact an attorney in your area<\/a>.<\/em><\/p>\n\n <\/div>\n <\/details>\n<\/section>\n

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The insanity defense is perhaps the most controversial of all criminal defense strategies. It’s also one of the least used and least successful defenses. Despite this, several successful uses of the defense have caused public outrage in the United States and the United Kingdom. In some cases, it led to reforms of the defense.<\/p>\n\n <\/div>\n\n

The insanity defense has roots in ancient Rome and Greece and has evolved over time. Today, most states use one of two insanity defenses, described below<\/p>\r\n

This article describes the basis for the\u00a0insanity defense<\/a>. It then provides a brief history of the defense’s evolution from ancient to modern times. The article concludes with several reforms proposed by critics of the insanity defense.<\/p>\r\n

Because the insanity defense is rare and difficult, defendants usually need a highly skilled criminal law attorney<\/a> to develop a successful strategy.\u00a0<\/p>\r\n

The Basis for the Insanity Defense<\/h2>\r\n

The insanity defense asserts that a\u00a0criminal defendant<\/a>\u00a0is not criminally\u00a0liable<\/a>\u00a0for their illegal acts due to their insanity. Insanity, in this context, refers to a specific mental illness or mental disorder.<\/p>\r\n

A defendant\u00a0asserting<\/a>\u00a0an insanity defense doesn’t argue whether they committed the alleged crime. Instead, the defense is whether the law should hold them liable for their criminal behavior since they did not have the\u00a0mental state<\/a>\u00a0to commit the crime.<\/p>\r\n

In criminal law, the\u00a0prosecution<\/a>\u00a0has the\u00a0burden of proof<\/a>\u00a0in proving a criminal is guilty\u00a0beyond a reasonable doubt<\/a>. Most crimes require the prosecution to prove two things:<\/p>\r\n