Witnesses: What Makes an Expert?

When an expert witness takes the stand to testify, he is a courtroom performer with an important privilege. Other witnesses are allowed to deal only with facts they have observed; the expert is often there to present his opinions and conclusions as well. At the trial of Jack Ruby, the experts had a field day.

Actually, as District Attorney Henry Wade explained afterward, the real expert witness in the Ruby trial was not a specialist but a policeman. The prosecution clinched its case by showing premeditated intent: Ruby, so the officer testified, had said: "I hope I killed the son of a bitch! I intended to shoot him three times."

It was Defense Attorney Melvin Belli who needed the expert witnesses, for Belli based his case on the argument that Jack Ruby was insane when he shot Lee Harvey Oswald. Belli produced a clutch of top psychologists and psychiatrists, all of whom testified that they had found something mentally or emotionally wrong with the defendant. The prosecution brought in its own squad of equally expert professionals, who testified to the contrary. Rebuttal was met with counterrebuttal and the witnesses were cross-examined till they were crosseyed. At the last minute, Belli put in a rush call to Chicago, persuaded Neurologist Frederic A. Gibbs—who had been reluctant to testify—to fly immediately to Dallas to help the defense. Gibbs got on the stand and said that Ruby was a victim of psychomotor variant epilepsy, characterized by "lack of emotional control—impulsive and obsessive types of behavior."

District Attorney Wade and his assistant William Alexander had a few other experts waiting in New York, but never felt it necessary to call them in. Their own counterexperts had performed extremely well. As for the rest, Wade and Alexander merely made their most telling points by demolishing opposition witnesses one by one.

Parolee & Physicist. The Ruby trial was a prime example of the problem expert witnesses pose for the jury—the often agonizing choice amateurs must make between the opposed opinions of two squads of specialists. With the use of expert testimony becoming commonplace in many kinds of cases, the battle of the experts and their rival qualifications is often decisive. An expert may be anyone from a paroled moonshiner to a nuclear physicist: what matters to the law is that he testifies about things that are peculiarly within his professional province.

What matters to lawyers, in addition, is the effectiveness of the expert's presentation to the jury. Not all experts, to be sure, will have the shock value of the legendary Perry W. Fattig of Atlanta. A shy entomologist, Fattig practically made a second profession of taking the stand when soft-drink bottlers were sued when bugs were found in their beverages. Expert Fattig would explain that eating an insect could be harmless, then he would plop a live roach in his mouth and chew it up. The demonstration was invariably impressive, but most trial lawyers agree with San Francisco's Jake Ehrlich, who looks not for stuntmen but for experts with "a pleasant demeanor, good solid judgment, some learning, and the sense to keep quiet at the right time."