THE (UN)CREDIBLE EXPERT WITNESS: THE IMPORTANCE OF TRUSTWORTHINESS AND EXPERTISE IN EXPERT WITNESS TESTIMONY

Abstract

The credibility of an expert witness is an important factor on the attitudes and behaviors of jurors. This study was conducted to investigate the relationship trustworthiness and expertise had on participants' verdict decisions, perceptions of expert witness overall credibility and each of the four separate dimensions of expert witness credibility. An audio recording presented an attack on the expert, showing him to be low in trustworthiness, low in expertise, low in both, or a control of neither. Dependent variables were participants' verdict decision of Likelihood of Negligence, and perceptions of credibility. Low trustworthiness and low expertise both significantly affect participants' verdict decision. Only the trustworthiness dimension affected participants' perception of overall credibility and trustworthiness, suggesting trustworthiness be treated as an independent dimension. Results further the construct of expert witness credibility and show trustworthiness and expertise to be important elements of expert witness credibility.