Section 17.43 Civil Cases

• Library: Evidence 2017

A. (§17.43) Civil Cases

Wide latitude is allowed in the cross-examination of expert witnesses. Stafford v. Lyon, 413 S.W.2d 495, 499 (Mo. 1967). The expert witness’s “credibility, skill or knowledge and the value and accuracy of his opinion” may be called into question during cross-examination. Stafford, 413 S.W.2d at 499.

Many matters may be addressed in the cross-examination of an expert witness. These matters do not need to have been addressed in direct examination. Conway v. Metro. St. Ry. Co., 142 S.W. 1101, 1103 (Mo. App. W.D. 1912). Not only are there few limits on the attack permitted in cross-examination, practitioners are permitted to dig into an expert’s past to attack the expert’s credibility. For example, in Nelson v. Waxman, 9 S.W.3d 601 (Mo. banc 2000), the Court permitted questions on cross-examination revealing that an expert witness failed a board certification examination in the past. But it should be noted that the party offering the expert had “opened the door” to the cross-examination by, among other things, implying that the only reason he was not board certified was that the board examination was not available to him. This example...