Evaluators’ Internal Norms in Forensic Assessment: Expected Psychopathy Checklist-Revised Scores as an Example

This study explored forensic evaluators' pre-evaluation expectations as a potential contributor to differences in decision-making. Evaluators estimated "typical" Psychopathy Checklist-Revised scores for different types of offenders. Score estimates varied substantially, particularly for sex offenders with child victims, ranging from as high as 35 (98th percentile) to as low as 10 (9th percentile). More experienced evaluators expected lower scores, but there was still clear variability in expectations among the most experienced evaluators. Correlations between the estimates and the scores evaluators assigned in four subsequent cases suggest expectations may operate as internal norms that anchor the scores they assign in individual cases.