Psychiatric assessment is likely to be the most useful for defendants under charges of arson, assault or attempted homicide, as these groups are most likely to suffer from a psychiatric disorder related to the alleged offence. Psychotic, organic and some developmental disorders appear to have the strongest relationship with diminished accountability. Findings with respect to illicit drug use are likely to have more varied implications between jurisdictions but, in the Netherlands, may sometimes be accepted as diminishing accountability in defendants of arson.

When comparing various indicators or treatment outcome, statistical considerations designate continuous outcomes, such as the effect size of the pre-post change (effect size or ΔT) as the optimal choice. Expressing outcome in proportions of recovered, changed, unchanged or deteriorated patients has supplementary value, as it is more easily interpreted and appreciated by clinicians, managerial staff and, last but not the least, by patients. If categorical outcomes are used with small datasets, true differences in institutional performance may get obscured due to diminished power to detect differences. With sufficient data, outcome according to continuous and categorical indicators converge and lead to similar rankings of institutes' performance.

In many jurisdictions, offenders need to have freely chosen to commit their crimes in order to be punishable. A mental defect or disorder may be a reason for diminished or total absence of criminal responsibility and may remove culpability. This study aims to provide an empirically based understanding of the factors on which experts base their judgements concerning criminal responsibility. Clinical, demographic and crime related variables, as well as MMPI-2 profiles, were collected from final reports concerning defendants of serious crime submitted to the observation clinic of the Dutch Ministry of Justice for a criminal responsibility assessment. Criminal responsibility was expressed along a five-point scale corresponding to the Dutch legal practice. Results showed that several variables contributed independently to experts' opinions regarding criminal responsibility: diagnosis (Axis I and II), cultural background, type of weapon used in committing the crime, and whether the defendant committed the crime alone or with others. In contract to jurisdictions involving a sane/insane dichotomy, the Dutch five-point scale of criminal responsibility revealed that Axis II personality disorders turned out to be mostly associated with a diminished responsibility. MMPI-2 scores also turned out to have a small contribution to experts' opinions on criminal responsibility, independently of mere diagnostic variables. These results suggest that experts base their judgements not only on the presence or absence of mental disorders, but also on cultural and crime related characteristics, as well as dimensional information about the defendant's personality and symptomatology.

No abstract

In a first study to compare subgroups of offenders with psychosis directly with non-psychotic offenders and non-offenders with psychosis, we found such additional support for a distinction between early and late starters with psychosis that different treatment strategies would seem indicated, focusing on personality and substance misuse for the former but psychotic symptoms for all. It remains to be seen whether the higher rate of alcohol misuse amongst late first offenders is a fundamental distinction or a function of age difference.