Our judges and lawyers seem slow to recognize the fact that the duties of experts are judicial, or at least quasi-judicial; to pass upon certain facts which neither the court nor the jury can understand without their aid. But, as we have seen from the citations just given, judges and lawyers have fully recognized the unreliability of expert testimony, produced as it now is in England and in this country at the whim and selection of the parties and paid for, much or little, according to the means of the parties.[181] _Method of Preliminary Examination of Experts—On Medical Questions a Licensed Physician Presumed Competent._—As the system exists here, the only power that the court has over the selection of an expert, is to determine, in advance of his testimony and of the elucidation of his opinions, whether or not he is competent as an expert. But this power affords little or no check or restriction, because in the effort to get all the light that is possible upon the questions under consideration, and to avoid unduly interfering with counsel in the conduct of the case at bar, the practice has become universal, and is recognized in the decisions and text writers, of permitting any medical man who has a license to practise his profession, to testify as an expert, and to give his opinion as such on any question cognate to his profession. This is so without regard to the amount of study and experience he may have had in the particular matter under consideration. The naked fact that he is licensed to practise is enough. He then—that is, after testifying that he is a practising physician—is clothed with the garment of authority. The only way in which his knowledge can be tested is by cross-examination as to his experience and skill, and possibly by contrasting him as he appears upon the witness-stand and his history as he gives it, with other and more or less experienced and skilful men who follow him.