Psychopathy, Moral Understanding and Criminal Responsibility

In Scotland and England individuals cannot be relieved from criminal responsibility on the basis that they have psychopathic personality disorder. The insanity defence in England is due to be reformed and, if the Law Commission’s proposals are implemented, it is likely that psychopaths will continue to be excluded from that defence. However, some philosophers and neuroscientists have argued that psychopaths should be entitled to a defence, as psychopathy can undermine a person’s ability to understand the wrongfulness of criminal conduct. This article will focus on empirical evidence, including findings from neuroscience, which lends some support to this argument. It will argue that brain scans, autonomic testing, interviews and cognitive tests suggest that psychopaths’ moral reasoning is impaired. Such evidence should be placed before the jury so that the jury can decide on a case-by-case basis whether individuals with psychopathy should be relieved from criminal responsibility.