CULPABILITY COMPARED: MENTAL CAPACITY, CRIMINAL OFFENCES AND THE ROLE OF THE EXPERT IN COMMON LAW AND CIVIL LAW JURISDICTIONS

Abstract: This article compares the situation in which an individual with diminished mental capacity is prosecuted for a criminal offence in England and Wales and in the Netherlands, with a particular focus on the role of the expert medical witness. It is not unreasonable to assume that, whatever the jurisdiction, the existence of a condition affecting the mental capacity of the defendant may affect how the culpability of the accused is assessed by the courts and translated into a verdict. By comparing culpability in the context of the role of experts, consideration will be given to how substantive and procedural law hang together in the different jurisdictions. A comparison between England and Wales (as an example of a common law jurisdiction) and the Netherlands (as an example of a civil law jurisdiction) may reveal very different outcomes with regard to the verdict and the way it is reached that have far-reaching consequences for the person involved. This article will examine why such differences may occur, in particular whether they are the result of the common law’s reliance on just two possible reasons for the absence of culpability in such cases (insanity or automatism, or, conceivably, diminished responsibility if murder is the charge), while the civil law is based on a theoretically underpinned doctrine that allows for a greater range of defences with regard to culpability (and its relative absence) in general. The topic not only has possible practical implications, but could also contribute to the growing body of comparative scholarship: comparisons of substantive criminal law, unlike its many procedural aspects, are few and far between. One of the reasons is that substantive law is shot through with moral considerations that are very diffi cult to ascertain and muddy the comparative waters considerably. In this case, however, the issue is not the offence itself, but whether and how a mental condition may affect culpability. While it could be said that the recognition of such conditions is also contingent on their social and moral connotations, the effect of this is likely to be much less than in a comparison of (perpetrators) of sexual offences per se.

Keywords: comparative criminal law; mental capacity; criminal liability; experts in criminal process; mental condition defences