Empirical research on the insanity defense and attempted reforms: evidence toward informed policy

Law Hum Behav. 1999 Jun;23(3):375-93. doi: 10.1023/a:1022364700424.


The paper addresses some common questions about the insanity defense and issues raised by commonly proposed "reforms." The first section begins with a brief description of the insanity defense and the reasons for its existence in the law. It then examines some of the popular myths and public misperceptions surrounding the insanity defense. The next three sections discuss proposed "reforms" and the empirical research that addresses their effect. These reforms, including various procedural changes in definitions, burden of proof, and expert testimony, the institution of a guilty but mentally ill verdict, and the abolition of the insanity defense itself, are reviewed, along with relevant research findings and policy issues. Finally, the development of sound conditional release programs for criminal defendants found not guilty by reason of insanity is proposed as a reform option which could serve the objectives of enhancing public safety and access to appropriate treatment while continuing to meet the objectives of the insanity defense within criminal jurisprudence.

Publication types

  • Corrected and Republished Article
  • Review

MeSH terms

  • Expert Testimony
  • Homicide / legislation & jurisprudence
  • Humans
  • Insanity Defense* / statistics & numerical data
  • Public Opinion
  • Public Policy*
  • Research
  • United States