Expert witness perceptions of bias in experts.

A pilot study of perceptions of different sources of expert bias, as well as of personal investment in case outcomes, was performed among attendees at a workshop at an annual meeting of the American Academy of Psychiatry and the Law. Participants were asked to rate hypothetical responses by experts to various case outcomes and the biasing potential of different kinds of situations for opposing or other experts. A factor analysis produced two factors. Factor 1 included questions about situations that were obviously biasing (such as working only for the defense). Factor 2 included questions assessing the potential of certain situations to cause bias in experts, or how likely experts thought other experts were to be biased. In general, experts identified only four areas to be overtly biasing. All occurred within situations in which experts worked only for one or the other side of civil or criminal cases. Experts otherwise thought other experts were reasonably bias free and well able to compensate for any bias when it occurred. The data suggest that experts may deal with bias by turning down cases that may cause them personal discomfort.