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 difficult 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.
The situation in which a person commits a criminal offence while affected by a condition that influences their (mental) capacity to act and, more importantly, to understand the implications of their actions, can occur, we may presume, in any country and therefore under any jurisdiction. That condition may be an inherent medical or mental problem (temporary or otherwise), it may be caused by ingesting certain substances (alcohol, drugs, medication), by other external factors such as extreme fear or distress or by a combination of any or all of these factors. It is also not unreasonable to assume that, whatever the jurisdiction, the existence of the condition will affect how the culpability of the accused is assessed by the courts and incorporated into the verdict.
While the outcome of a trial is a legal matter and culpability a normative legal concept, the question of whether a defendant lacks (a degree of) mental capacity is not in itself one that judges or average members of a jury are trained to answer. Experts such as psychologists and psychiatrists therefore play an important role in helping determine whether a defendant (1) suffers (or suffered at the time of the offence) from any medical and/or mental problem and (2) what the effect of that problem was on their capability to act and to know or correctly assess the consequences of their actions. So, the necessity of calling in the assistance of experts is also a feature of all jurisdictions if the defendant raises a defence that calls his mental capacity, and thus culpability, into question.
However, even a superficial comparison between common law and civil law jurisdictions reveals that there are some major differences in both how experts define mental conditions and how courts translate these situations into the possibility that the defendant should not be held responsible under the law for what they have done. Such differences influence the verdict and have far-reaching consequences for the person involved. This article examines the factors that affect the occurrence of these discrepancies, drawing on (case) law and (court) practice in England and Wales as an example of a common law jurisdiction with an adversarial trial mode, and from the civil law jurisdiction of the Netherlands, where the mode of trial is predominantly inquisitorial.
Our topic — capacity, culpability and the role of the expert — 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 cultural-moral considerations that are very difficult to ascertain and muddy the comparative waters considerably. In this case, however, we are not concerned with the offence itself, but with whether and how a mental condition may affect criminal liability, and the reasons for and consequences of differences between jurisdictions. We are also concerned with the relationship between these substantive questions and the procedural issue of the expert at trial. Although it could be said that how such conditions are or are not recognised and defined in law 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 criminal offences per se. In any event, comparing culpability in the context of the role of experts will hopefully shed some light on how substantive and procedural law hang together in different jurisdictions, thus providing a framework for determining whether changes — be they substantive or procedural — are feasible. As always in a comparative study, a caveat is in order with regard to language. The use of English, although the most widely accepted lingua franca of the academic world, complicates matters, for it is also the language of the common law. English words in a legal context therefore refer to common law concepts, but may mean something quite different in the civil law world. Sometimes, the concept to which an English word refers derives its meaning from the specific adversarial style of the criminal process that is characteristic of the common law and simply does not, or rather cannot, exist in the inquisitorial process. A guilty plea in the English (or American) sense, for example, is never entered in the Netherlands and means nothing in the Dutch context, simply because defendants do not plead in order to end the trial process; they may confess, but the court will still go on to investigate the case — the confession being no more than a piece of evidence, albeit an important one. Sometimes the words appear to mean the same thing, but have different connotations or consequences that relate to differences in procedure (eg prosecutor, witness, impartiality), or in substantive law (eg murder, manslaughter, intent, self- defence). We have tried to avoid the misunderstandings that such discrepancies may cause by explaining, where necessary, the wider context in which concepts are embedded and from which they draw their specific meaning.
In the following, we first explore the differences between the Netherlands and England and Wales with regard to matters of mental capacity and criminal liability. We then look more closely at the role played by experts in helping the court reach a verdict. Given the differences between the jurisdictions that are immediately obvious, our first question is whether these are the result of the common law’s reliance on just two possible reasons for the absence of culpability (insanity or automatism, or 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. This is further compounded by the issue of “fitness to plead”, which, while it appears to exist in Dutch law, is actually a different concept with different connotations (and consequences). An additional reason to compare these two countries is that, despite substantive legal and procedural differences, in the field of forensic mental health, both countries are eager to know and learn from each other’s system. Most interest from abroad in the Dutch forensic mental health system stems from the United Kingdom.2 Recent innovations in the UK were inspired by the program and system in the Netherlands: the Medium Secure Units and the Dangerous and Severe Personality Disorder program are recent examples in the UK, while in the 1960s, Maxwell Jones’s therapeutic community model was followed in Dutch forensic treatment hospitals.
Two major interrelated questions then arise. The first concerns the concept of capacity and culpability in substantive law, and how this relates to specific defences. Could it be that experts define conditions in a way that allows them to be translated into what the law and the courts require? In other words, what is the relationship between the empirical knowledge of the psychologist or psychiatrist and the normative demands of the criminal law? The second question is related to differences in procedural styles. The position and role of the expert in an adversarial and inquisitorial trial setting, respectively, differ significantly. Could the fact that the expert in the Netherlands is appointed to the court, not as a witness but in a specific and legally defined role (and moreover, since recently, needs to be included in the official register of court experts), promote both greater consensus and a more specific, individual-based approach to defences regarding mental capacity than is possible in a jurisdiction where expert witnesses in an adversarial trial appear for either the defence or the prosecution?