Capacitas Ex Machina : Are Computerised Assessmets of Mental Capacity a Benchmark or 'Red Line' for Artificial Intelligence?

This paper traces the history of computers in medicine, focusing on the rise of Expert Systems (ES) in the mid-20th century, to the rise of connectionist AI research in its latter half, and ultimately the development of Automated Mental State Detection (AMSD), fMRI scanning, and human brain interfaces.Following the critique of Joseph Weizenbaum in Computer Power and Human Reason (1976), the paper examines theoretical, practical, and ethical problems for implementing these systems in the real world, and how mental health law and psychiatry are likely to be impacted by near term technological advances which will increasingly 'objectify' the diagnosis and treatment of mental disorders.It concludes with a discussion for how computational reasoning could--and indeed should--operate in the context of mental capacity decisions in England and Wales, and suggests that the use of machines to assess mental capacity should be a "Red Line" for the ingress of AI and related technologies. It concludes with reflections on the legal implications of this claim, and identifies opportunities for further research