Justice Potter Stewart famously quipped that although he could not define pornography, “I know it when I see it.” Jacobellis v. Ohio, 84 S.Ct. 1676, 1683 (1964). Bias presents the opposite problem. It can be readily defined but you do not necessarily know it when you see it. Given that custody evaluators are as susceptible to bias as anyone else and because bias can destroy the reliability of their conclusions, it is imperative that lawyers and judges be able to recognize its telltale signs. While “there is no blood test for evaluator bias,” (J.P. Wittmann, “Evaluating Evaluations: An Attorneys Handbook for Analyzing Child Custody Reports” (MatLaw Systems, 2013, p. 160)), it can be inferred from the evaluator's methods and behaviors. This article will delineate some key indicators that can help legal professionals spot bias in forensic assessments.

Key Indicator #1: Infidelity to Science

No small part of a psychologist's education is devoted to understanding the limitations of psychological knowledge and the overarching importance of constricting professional conclusions to those that are supportable by the published knowledge-base of the profession.

This concept of constraint is inherent in the profession's self-definition as a “scientific” field. Pick up any standard university Psych 101 textbook and you will find that psychology defines itself as “the scientific study of human behavior and mental processes.” C. G. Morris and A.A. Maisto, “Psychology: An Introduction,” (Prentice Hall, 11th Edition, 2002), at p. xii. Remove the word “scientific” from that definition and you are no longer talking about psychology. When psychology emerged in the 19th century as a distinct discipline, independent of its intellectual cousin philosophy (defined by Merriam-Webster as “a search for a general understanding of values and reality by chiefly speculative rather than observational means), its defining attribute was its commitment to the scientific method. It essentially guaranteed the public that “the conclusions about behavior that it produces derive from scientific methods” and that its work product has been “derived from and tested by scientific methods.” K.E. Stanovich, “How to Think Straight About Psychology,” 10th ed., p. 6 (Pearson, 2013).