In a case of murder, to which the defence of insanity was set up, a medical witness called on behalf of the accused swore that in his opinion the accused, at the time he killed the deceased, was affected with a homicidal mania, and urged to the act by an _irresistible_ impulse. The judge, not satisfied with this, first put the witness some questions on other subjects, and then asked, "Do you think the accused would have acted as he did if a policeman had been present?" to which the witness at once answered in the negative. Thereupon the judge remarked, "Your definition of an irresistible impulse must then be an impulse irresistible at all times except when a policeman is present."
CROSS-EXAMINATION OF THE PERJURED WITNESS
In the preceding chapters it was attempted to offer a few suggestions, gathered from experience, for the proper handling of an honest witness who, through ignorance or partisanship, and more or less unintentionally, had testified to a mistaken state of facts injurious to our side of the litigation. In the present chapter it is proposed to discuss the far more difficult task of exposing, by the arts of cross-examination, the intentional Fraud, the perjured witness. Here it is that the greatest ingenuity of the trial lawyer is called into play; here rules help but little as compared with years of actual experience. What can be conceived more difficult in advocacy than the task of proving a witness, whom you may neither have seen nor heard of before he gives his testimony against you, to be a wilful perjurer, as it were out of his own mouth?
It seldom happens that a witness's entire testimony is false from beginning to end. Perhaps the greater part of it is true, and only the crucial part--the point, however, on which the whole case may turn--is wilfully false. If, at the end of his direct testimony, we conclude that the witness we have to cross-examine--to continue the imaginary trial we were conducting in the previous chapter--comes under this class, what means are we to employ to expose him to the jury?
Let us first be certain we are right in our estimate of him--that he intends perjury. Embarrassment is one of the emblems of perjury, but by no means always so. The novelty and difficulty of the situation--being called upon to testify before a room full of people, with lawyers on all sides ready to ridicule or abuse--often occasions embarrassment in witnesses of the highest integrity. Then again some people are constitutionally nervous and could be nothing else when testifying in open court. Let us be sure our witness is not of this type before we subject him to the particular form of torture we have in store for the perjurer.