When no other defence to homicide is possible the claim of insanity is frequently interposed. Nothing is more confusing to the ordinary juryman than trying to determine the probative value of evidence touching unsoundness of mind, and the application thereto of the legal test of criminal responsibility. In point of fact, juries are hardly to be blamed for this, since the law itself is antiquated and the subject one abounding in difficulty. Unfortunately the opportunity for vague yet damaging testimony on the part of experts, the ease with which any desired opinion can be defended by a slight alteration in the hypothetical facts, and the practical impossibility of exposure, have been seized upon with avidity by a score or more of unscrupulous alienists who are prepared to sell their services to the highest bidder. These men are all the more dangerous because, clever students of mental disease and thorough masters of their subject as they are, they are able by adroit qualifications and skilful evasions to make half-truths seem as convincing as whole ones. They ask and receive large sums for their services, and their dishonest testimony must be met and refuted by the evidence of honest physicians, who, by virtue of their attainments, have a right to demand substantial fees. Even so, newspaper reports of the expense to the State of notorious trials are grossly exaggerated. The entire cost of the first Thaw trial to the County of New York was considerably less than twenty thousand dollars, and the second trial not more than half that amount. To the defence, however, it was a costly matter, as the recent schedules in bankruptcy of the defendant show. Therein it appears that one of his half-dozen counsel still claims as owing to him for his services on the first trial the modest sum of thirty-five thousand dollars! The cost of the whole defence was probably ten times that sum. Most of the money goes to the lawyers, and the experts take the remainder.

It goes without saying that both prosecutor and attorney for the defence must be masters of the subject involved. A trial for poisoning means an exhaustive study not only of analytic chemistry, but of practical medicine on the part of all the lawyers in the case, while a plea of insanity requires that, for the time being, the district attorney shall become an alienist, familiar with every aspect of paranoia, dementia præcox, and all other forms of mania. He must also reduce his knowledge to concrete, workable form, and be able to defeat opposing experts on their own ground. But such knowledge comes only by prayer and fasting—or, perhaps, rather by months of hard and remorseless grind.

The writer once prosecuted a druggist who had, by mistake, filled a prescription for a one-fourth-grain pill of calomel with a one-fourth-grain pill of morphine. The baby for whom the pill was intended died in consequence. The defence was that the prescription had been properly filled, but that the child was the victim of various diseases, from acute gastritis to cerebro-spinal meningitis. In preparation the writer was compelled to spend four hours every evening for a week with three specialists, and became temporarily a minor expert on children’s diseases. To-day he is forced to admit that he would not know a case of acute gastritis from one of mumps. But the druggist was convicted.

Yet it is not enough to prepare for the defence you believe the accused is going to interpose. A conscientious preparation means getting ready for any defence he may endeavor to put in. Just as the prudent general has an eye to every possible turn of the battle and has, if he can, re-enforcements on the march, so the prosecutor must be ready for anything, and readiest of all for the unexpected. He must not rest upon the belief that the other side will concede any fact, however clear it may seem. Some cases are lost simply because it never occurs to the district attorney that the accused will deny something which the State has twenty witnesses to prove. The twenty witnesses are, therefore, not summoned on the day of trial, the defendant does deny it, and as it is a case of word against word the accused gets the benefit of the doubt and, perhaps, is acquitted.

No case is properly prepared unless there is in the court-room every witness who knows anything about any aspect of the case. No one can foretell when the unimportant will become the vital. Most cases turn on an unconsidered point. A prosecutor once lost what seemed to him the clearest sort of a case. When it was all over, and the defendant had passed out of the court-room rejoicing, he turned to the foreman and asked the reason for the verdict.

“Did you hear your chief witness say he was a carpenter?” inquired the foreman.

“Why, certainly,” answered the district attorney.

“Did you hear me ask him what he paid for that ready-made pine door he claimed to be working on when he saw the assault?”

The prosecutor recalled the incident and nodded.

“Well, he said ten dollars—and I knew he was a liar. A door like that don’t cost but four-fifty!”