Retainer Bias: Ethical and Practical Considerations for the Forensic Neuropsychologist.

How is it that practicing forensic neuropsychologists occasionally see substandard work from other colleagues, or more fundamentally, have such disparate opinions on the same case? One answer might be that in every profession, competence varies. Another possibility has little to do with competence, but professional conduct. In this paper we discuss the process by which retainer bias may occur. Retainer bias is a form of confirmatory bias, i.e., in assessment, the tendency to seek, favor, and interpret data and make judgments and decisions that support a predetermined expectation or hypothesis, ignoring or dismissing data that challenge that hypothesis ( Nickerson, 1998). The tendency to interpret data in support of the retaining attorney's position of advocacy may be intentional - that is, within conscious awareness and explicit, or it may be unintentional, outside of one's awareness, representing implicit bias. While some practitioners accept referrals from both sides in litigation, numerous uncontrollable factors converge in such a manner that one's practice may nevertheless become associated with one side. Such imbalance is not a reliable index of bias. With brief hypothetical scenarios, in this paper we discuss contextual factors that increase risk for retainer bias and problematic practice approaches that may be used to support one side in litigation, violating ethical principles, codes of conduct and guidelines for engaging in forensic work. We also discuss debiasing techniques recommended within the empirical literature and call on the subspecialty field of forensic neuropsychology to conduct research into retainer bias and other sources of opinion variability.