Details

Autor(en) / Beteiligte

• Pirelli, Gianni

Titel

A meta-analytic review of competency to stand trial research

Ort / Verlag

ProQuest Dissertations & Theses

Erscheinungsjahr

2010

Quelle

ProQuest Dissertations & Theses A&I

Beschreibungen/Notizen

• The notion that an individual must be competent to stand trial dates back to 14th century England and has been well documented in English case law. The competency standard in the United States was derived from Dusky v. United States (1960). Since the 1960s the number of empirical investigations in this area of research has grown considerably. It is essential for applied empirical research to be conducted to provide policy makers, practitioners, and psycholegal researchers with the most useful and updated information available. A meta-analysis accomplishes this goal. Such research also has important implications for criminal defendants, as they have the most at stake in competency evaluations. The present study is a meta-analysis of competency to stand trial research. Only one meta-analysis, published nearly 20 years ago, has been conducted in this area. Since then over 100 empirical research studies have been conducted and eight competency instruments have been either published or revised. This paper presents the results of a meta-analysis of 68 studies, conducted between 1967 and 2008, comparing competent and incompetent defendants on a number of demographic, psychiatric, and criminological variables. Categorical (e.g., psychiatric diagnosis) and continuous (e.g., scores on traditional and competency assessment measures) variables commonly investigated in competency research were coded and aggregated to generate cumulative effect sizes and moderation was formally tested via meta-F and meta-regression analyses. The most robust findings associated with these variables were that defendants diagnosed with a Psychotic Disorder were approximately eight times more likely to be found incompetent than defendants without such a diagnosis and the likelihood of being found incompetent was approximately double for unemployed defendants as compared to employed defendants as well as those with a previous psychiatric hospitalization versus those without such a history. Comparative data on 12 competency measures, the Wechsler intelligence scales, and the MMPI/MMPI-2 was also explored. The effect sizes associated with the competency measures were larger than those for the traditional measures; however, the findings must be cautiously interpreted because few studies with relatively small sample sizes were included in the analyses. Implications of these findings for research and practice will be discussed.