The Medical Expert and the Legal Examiner. ity. In every sensational case and mysteri ous murder investigation, the inevitable lunatic appears and discloses his strange story, his wild vagaries and suggestive hal lucinations to increase the doubt, while Dame Rumor reels off her endless yarns of fabrication, to be tested and destroyed by the cross-examiner's work. When we con sider these facts, and take into account that further fact, as Shakespeare puts it, " How the world is given to lying," can there be any question as to the utility and necessity of the cross-examiner's art? The courts eould dispense with the bailiff, the clerk, the stenographer, and often with the jury, on the trial, without prejudice to truth and justice, but not with the cross-examiner. The surgeon uses the knife not to wound the patient, but to sever the connection, and to separate the cancerous tumor from the healthy tissue, as the means of restoring health, and prolonging life. In like man ner the lawyer uses the cutting blade of cross-examination, not to hurt the witness, but to sever the connection, and to separ ate the festering falsehood from the sacred truth, as a means of protecting rights, and of securing justice. The pain produced in both cases is an incident, and not an end. As long as flesh and blood are liable to ac cident and disease, will the surgeon's knife be required to prevent suffering, restore health, and prolong life; and so long as human nature remains imperfect and de ceitful, will the cross-examiner's blade be required to detect error, preserve rights, and enforce justice. Expert witnesses are usually selected in consequence of their avowed opinions upon the questions involved, for the purpose of sustaining the contention of the party call ing them. While in appearance, they speak ex eathedra, and are produced as authority, and are frequently accepted as such by court and jury, nevertheless, in fact, they are identified with one side of the case, and too often are interested allies to it, which has a
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tendency to impair the weight of all expert testimony. Such experts "being zealous partisans, their belief becomes synonymous with faith as defined by the apostle, and it too often is but the substance of things hoped for, the evidence of things not seen." But witnesses are never compelled to stultify or to perjure themselves. "No one who is ignorant of a thing is bound to give informa tion of it; but every one is bound to know that which he gives information of." Nemo tenetur informare qui neseit, sed quisquis seire quod informat. The expert witness, being called and often accepted as authority upon matters not generally understood by the jury, is required by common honesty and the public welfare to know the scientific facts involved in the case, and in an impar tial and judicial manner declare the truth without fear or favor. The hypothetical question must be based upon the testimony produced on the trial. This testimony is fragmentary, variant, con flicting and often inconsistent and contra dictory: nevertheless the court and jury must determine the facts from these ele ments. The medical expert should remem ber that the various facts recited in the hypothetical question are changed to include the different phases of the testimony and the various theories of the case; and that these changes, with their inherent difficulties to him, are made necessary by the testimony and the issues. He should understand that if he would creditably answer these ques tions, his learning must be at command, and his mind so trained as to readily comprehend the different phases of the question, and to jjive a complete answer. The lawyer is not responsible for the different phases of the testimony, or the various theories of the case. The medical expert is required to answer these complex questions, and give opinions upon their different features and theories, for the purpose of throwing the light of medical science upon these diverse elements of the case. In deposing to these
