Insanity defense is a 19th century argument that protects persons from legal accountability for criminal actions due to unstable and irrational mental state. The jury’s decision on criminal commitment depends on the evaluation of an offender’s sanity and ability to stand trial. Insanity defense has undergone numerous changes since the M’Naghten case in which a person from a Troy party delusion killed the British prime minister’s secretary (Talbott & Hales, 2001). The jury in this case made a landmark ruling that created the foundation for an insanity defense. Provisions on the insanity defense have undergone modifications to address aspects that considerably limited the scope of liability of offenders with mental disorders. Mental health professionals feel the need to incorporate matters relating to mental illnesses that alter people’s cognitive and emotional abilities in the provisions for an insanity defense. Such modifications would ensure the consideration of all functional aspects relating to individual’s criminal responsibility. The Durham rule of 1954 played a crucial role in broadening the criteria for the insanity defense to include aspects of various mental defects. This rule prompted a reevaluation of the process of ascertaining the role of a person’s mental illness in the commission of a crime (Barlow & Durand, 2002). The ALI group comprising of several attorneys and law scholars emphasized on the need for distinct approaches concerning the trial of mentally ill offenders as the use of traditional methods for controlling crime would not deter criminal behaviors of such persons. This group also addressed issues relating to the role of mental illnesses in diminishing an individual’s ability to evaluate rationally his or her behavior. The modifications concerned insanity defense to create a framework that help to address the needs of mentally ill offenders. These modifications highlighted the need to provide treatment for offenders with mental disorders rather than focusing on punishing them, which would have little if any deterrent effect.