Dateline: October, 2008, Issue 4

What questioning style is most effective for discrediting an expert witness?

Attorneys can seek to discredit an expert witness in cross-examination by using (a) either leading or non-leading questions asked in (b) either a hostile or non-hostile style.

Gibbs and colleagues (1989) investigated how effective different questioning styles are when an attorney wants to discredit an expert witness during cross-examination. All jurors saw a videotaped reenactment of a personal injury case that included the cross-examination of an expert witness. One group of jurors saw an attorney cross-examining the expert with leading questions and a hostile questioning style (including angry voice inflection and pronounced hand gestures). A second group of jurors saw the same leading questions asked in a non-hostile style. Two other groups of jurors saw the attorney ask non-leading questions of the expert in either a hostile or non-hostile questioning style.

When the attorney was either too aggressive or too soft in his attempt to discredit the expert witness, jurors perceived the attorney as less convincing and effective. That is, the attorney was the least convincing and least effective when asking (a) leading questions in a hostile style or (b) non-leading questions in a non-hostile style; and the attorney was most convincing when asking (c) leading questions in a non-hostile style or (d) non-leading questions in a hostile style.

In this research, jurors' perceptions of the attorney were affected by his cross-examination style but their verdicts were unaffected by his questioning style.

In sum, jurors expect lawyers to be both lawyers and statesmen. The aggressiveness of a hostile questioning style can be offset by the use of non-leading questions, just as the use of leading questions can offset the softness of a non-hostile questioning style.

Source Gibbs, M.S., Sigal, J., Adams, B., & Grossman, B. (1989). Cross-examination of the expert witness: Do hostile tactics affect impressions of a simulated jury? Behavioral Sciences & The Law, 7, pp. 275-281.