Effects of the Presser and legislative criteria on classifying New Zealand's fitness to stand trial court outcomes.

New Zealand's legislation mandates the inclusion of several legislative criteria to assist in the determination of defendants' fitness to stand trial (FTST). However, the unlegislated Presser criteria have been described as useful to discriminate between defendants' fitness without formal research to identify them as such. The sample consisted of 252 defendants' FTST forensic assessments between 2005 and 2015 with a mean age of 30.1 years, where 87.7% were male. Defendants were primarily from Māori descent (37.3%), New Zealand European (34.1%) and Pacific Island descent (17.9%). The authors found that all Presser and legislative criteria significantly predicted whether the defendant was fit to stand trial (FST). Both the Presser and legislative criteria have excellent area under the curve (AUC) statistics. However, the Presser criteria, compared to the legislative criteria, improved specificity of court judgements. The Presser criteria may therefore assist in correct FTST court decisions, particularly for borderline-fit defendants.