'In a Kind of Mad Way': A Historical Perspective on Evidence and Proof of Mental Incapacity

Article excerpt

[This article examines the evidential and procedural aspects of claims based on mental incapacity in English courtrooms in the 'long' 18th century. It employs a frame the author has termed 'manifest madness' to analyse how such claims were articulated and elaborated at trial in this period This analysis reveals, first, the substantive significance of the accused's conduct; second, the part played by ordinary people; and third, the role of common knowledge of 'madness' in evidence and proof of mental incapacity for criminal law purposes. By reference to the law on what would now be called unfitness to plead, automatism and intoxication, this article demonstrates the utility of the 'manifest madness' frame for understanding the evidential and procedural practices attendant to mental incapacity claims in this period. The article then considers the insights this historical analysis provides into current criminal practices for proving mental incapacity.]


I    Introduction
II   A Historical Approach to Evidence and Proof of Mental Incapacity
     in Criminal Law
III  'Manifest Madness' Applied: Beyond the Bounds of Insanity in the
     'Long' 18th Century
        A   The Substantive Significance of the Accused's Conduct
        B   'Madness' Evident or Obvious to Ordinary People
        C   Common Knowledge of 'Madness'
IV Rethinking Evidence and Proof of Mental Incapacity


In criminal trials, when mental incapacity is raised--whether for the purposes of exculpation, partial exculpation or for some other reason, such as to prevent a normal trial proceeding--it is often assumed to introduce distinctive and difficult issues of evidence and proof. When used in a criminal law context, mental incapacity connotes the absence of or impairment in the cognitive, volitional and moral capacities that are both assumed and required by the criminal law. (1) Insanity enjoys the highest profile of mental incapacity doctrines,

and, as is well known, distinctive procedural and evidentiary rules attach to the doctrine. (2) Since the development of the modern insanity doctrine in the early 19th century, insanity has been thought to be difficult to prove for criminal law purposes. (3) Perhaps by analogy with insanity, other types of mental incapacity are also dogged by concerns about their provability. A suspicion that mental incapacity is distinctively opaque in epistemological terms seems to account in part for the now ubiquitous practice of relying on expert psychiatric and psychological evidence in trials where mental incapacity is at issue. Such evidence is adduced on the basis that knowledge of 'abnormal' mental states--unlike knowledge of 'normal' mental states--is beyond the reach of the jury, although the jury is then called on to assess that expert evidence. (4) Yet, even with the benefit of expert evidence, criminal law evaluation and adjudication practices based on mental incapacity seem unable to escape doubts about the genuineness of the particular mental condition as raised in court, and the legitimacy of any legal outcome based on a particular instance of incapacity. (5)

Although claims based on mental incapacity seem haunted by doubts about their genuineness and legitimacy, it is possible to point to an era in which such claims were not beset by concerns about their provability. A close study of that era provides a useful perspective on the evidentiary and procedural practices relating to mental incapacity, placing into temporal relief the concerns that have become quite familiar in the current era. As I discuss below, in that era-defined as approximately up to the end of the 18th century--both George Fletcher's paradigm of 'manifest criminality' and my own 'manifest madness' frame assist in understanding the evaluation of criminality and mental incapacity, respectively. In this article, my analysis, which has been inspired by Fletcher's, is tested against evidentiary practices governing the law relating to unfitness to plead, automatism and intoxication. …