Abstract
The
legal concept of insanity spans more than a thousand years. Concurrently, our
understanding of neuropathology has continuously evolved. Psychological
knowledge has resulted in reformulations of the insanity defence, and spawned
the defences of diminished capacity and diminished responsibility, offshoots of
the insanity defence. As the study of
neurobiology flourishes, evidence is multiplying that important aspects of
behaviour can be affected via involuntary exposure to neuro-modulating
substances with wide-ranging results, from severe psychiatric disturbances to
murderous rage. But the inherent complexities of defining insanity are
compounded by new insights into the workings of the human brain. This research uses the research methodologies
of both historical and doctrinal legal research. By looking back at the first
attempt at an involuntary neurotoxic damage defence, this paper investigates
the manner in which contemporary neuroscientific findings interface with the
traditional jurisprudence of criminal non-responsibility and provides a
guidepost for legal, scholarly, and forensic practitioners.