Kahler v. Kansas: The Constitutionality of Abolishing the Insanity Defense

Arguments for the abolition of the defence of mental impairment

This article summarises arguments for abolishing the mental impairment defence, using the example of the defence in Victoria, taking a historical and comparative approach. It considers the defence in practice, its origins and stagnation in medieval and Victorian England, a better approach based on modern developments in the UK and Europe, its resistance to meaningful reform, and its failure to achieve its laudable, humane and principled aim of sparing vulnerable people with severe mental health problems from punishment. We conclude that the only way to actually achieve this aim is to abolish the mental impairment defence and replace it with an approach that allows for flexible mental health disposals for mentally disordered offenders based on clinical needs and, where necessary, the need for containment, incorporated in and aligned with mental health legislation, regardless of culpability, and with modern systems and services that bring Victoria out of the nineteenth century.

Settled Insanity: Substance Use Meets the Insanity Defense

Mental impairments as a result of intoxication with alcohol or drugs have never been accepted as bases for an insanity defense. However, most U.S. jurisdictions have agreed that when the downstream effects of substance use lead to longer-term impairment, this circumstance can serve as legitimate grounds for an insanity plea. A recent Massachusetts case illustrates the application of this doctrine of "settled insanity." Although subject to criticism as excusing volitional behavior, recognition of the interplay between endogenous dispositions and the effects of substances suggests the wisdom of allowing settled insanity pleas.