Page:The Art of Cross-Examination.djvu/85

 experiment; and then only when the lawyer's research of the medical authorities, which he should have with him in court, convinces him that he can expose the doctor's erroneous conclusions, not only to himself, but to a jury who will not readily comprehend the abstract theories of physiology upon which even the medical profession itself is divided.

On the other hand, some careful and judicious questions, seeking to bring out separate facts and separate points from the knowledge and experience of the expert, which will tend to support the theory of the attorney's own side of the case, are usually productive of good results. In other words, the art of the cross-examiner should be directed to bring out such scientific facts from the knowledge of the expert as will help his own case, and thus tend to destroy the weight of the opinion of the expert given against him.

Another suggestion which should always be borne in mind is that no question should be put to an expert which is in any way so broad as to give the expert an opportunity to expatiate upon his own views, and thus afford him an opportunity in his answer to give his reasons, in his own way, for his opinions, which counsel calling him as an expert might not otherwise have fully brought out in his examination.

It was in the trial of Dr. Buchanan on the charge of murdering his wife, that a single, ill-advised question put upon cross-examination to the physician who had attended