Expert Psychological Testimony in the Capital Trial Penalty Phase: A Content Analysis of Trial Transcripts

ABSTRACT

We know little about what constitutes “typical” testimony offered by psychological experts in capital sentencing trials. Experts may address mitigating factors to the jury during the penalty phase, but the mitigators typically offered, as well as the evidence presented to support the relevance of the mitigators, remains poorly understood. A sample of 94 capital trial transcripts were content analyzed. Findings suggest that expert presence was unrelated to sentencing judgments. Analysis of testimony content revealed that testimony concerning childhood abuse, mental illness, and family issues (i.e., a parent in prison or witnessing domestic violence) occurred in over 50% of the cases involving experts and that intelligence tests and personality assessments were the most frequently used assessment tools. The type of mitigating evidence presented (i.e., whether the testimony focused on the individual’s characteristics or the environmental factors that influenced the individual during development) varied considerably across cases. Implications, limitations, and future directions are discussed.

KEYWORDS:

• Expert testimony
• forensic psychology
• capital trial
• clinical psychology
• content analysis

Disclosure statement

No potential conflict of interest was reported by the author(s).

Notes

¹ The unanticipated findings regarding the presence of expert witness and death penalty judgments prompted a follow up analysis to determine if the state in which the case took place may have masked significant findings (i.e., if expert testimony was predominantly present in states in which juries are more likely to render death penalty judgments). To control for this possibility, the number of executions that occurred in a 5-year time span leading up to the 2004 calendar year was assessed and this number was used as a covariate. A logistic regression examining expert testimony as the predictor and sentencing decision as the criterion was conducted using the number death penalty decisions for the state in which it occurred as the covariate. The logistic regression revealed the main effect for presence/absence of an expert was not significant when controlling for death-prone status of the state, Wald χ² = 1.82, p = .18. The covariate (number of death penalty decisions for the state was unrelated to sentencing, Wald χ² = .148, p = .70).

Additional information

Funding

This research was supported by an NSF grant (SES- 0851183) to the 2nd author and by an NSF grant (SES-0851004) to the 5th and 6th authors. Correspondence concerning this article should be addressed to Rachel Kantor, Department of Psychology, University of North Carolina Wilmington, 601 South College Rd., Wilmington, NC, 28403. Email: [email protected].