Evaluating Credibility of Witnesses – are We Instructing Jurors on Invalid Factors?

Co-author Aldert Vrij, Ph.D., an internationally respected expert on evaluating credibility and the European Consortium of Psychological Research on Deception Detection’s contact person, presented an educational lecture program concerning the fallacy of considering nonverbal behavior to evaluate credibility at the 2016 Pennsylvania Conference of State Trial Judges. Many of the judges listening to Dr Vrij, wondered why then, do judges consistently instruct jurors to consider demeanor and other nonverbal behaviors to evaluate witnesses’ credibility? Why do we ignore the overwhelming scientific evidence and continue to give jury instructions contrary to the overwhelming consensus that witness demeanor is not a basis to determine the accuracy or truthfulness of their testimony? Many years ago, co-author Jeannine Turgeon attended United States Supreme Court Justice Sandra Day O’Connor’s lecture “Trial by Jury–In Need of Repair” at The Chautauqua Institute. Justice O’Connor criticized various aspects of our current jury system and offered suggestions for its improvement. She opined that “[j]ust because something has ‘always been done’ a particular way does not mean that is the best way to do it. If common sense tells us to change something, we should change it.”