\S2 



NATURE 



[August 17, 1893 



and regulations of the court, with which he may not be familiar, 

 and, at the same time, possessing an undoubted influence with 

 a jury, that it is difficult to restrict by the established rules and 

 maxims of legal procedure." 



After a consideration of the circumstances that shape the 

 reputation of the scientific expert with the bar, bench, and laity 

 we read : — "In considering some of the sources of dissatisfaction 

 with the scientific experts, perhaps one of the first to suggest 

 itself, and one of the most prolific, is the vagueness of the legal 

 definition of the term 'scientific expert' before alluded lo, 

 but which on more careful consideration might rather be termed 

 vagueness and variableness of the standard. Definitions of 

 things are of ideals, and consequently definition is followed 

 closely by the statement that the thing defined is non-existent. 

 The ideal circle is defined, so the ideal solid, the ideal liquid ; 

 these definitions are only approached, never realised. Degrees 

 of approach constitute the differences. Practically the courts 

 are limited to the be-t experts extant in any field, though they 

 may at times fall far short of the ideal. But it is to be feared 

 that in many cases the experts fall below a reasonable and pos- 

 sible standard, and far below the standard that would le fixed 

 liy scientific men themselves, as well as below the exigencies of 

 the case. This may easily I e accounted for. A party presents 

 a witness as an expert. The judge must j ass upon his com- 

 petency upon such examination as he can make. That decision, 

 though not necessarily, nor even by unvarying practice, a matter 

 of discretion, will not often be reviewed by a superior court. 

 Often, then, the best solution, certainly the easiest, seems 

 to be to admit, even where there may be grave doubt 

 as to qualification, and to throw the burden upon the jury, 

 already overburdened with questions, which the theory of 

 trial by jury assigns them, questions which they are not 

 q vilified to deal with, although they may be fully up to the 

 average in general intelligence. At a time when experts 

 were not much beyond men in the ordinary avocations of life 

 it may have been reasonable to require the jury to pass upon 

 the ' weight and credit to be given to evidence viewed in con- 

 nection with all the circumstances,' b ;t under the changed 

 circumstances of to-day, with experts of a character, and upon 

 questions not dreamed of even a century ago, it seems to be 

 straining a theory too far to put upon an average jury the 

 decision of so grave a question, as to the character of the expert, 

 which the court may not be able to settle satisfactorily. But 

 for the theory it would not be thought of, if a system of 

 jurisprudence were now being devised. Now among the results 

 incidental to a liberal interpretation of the term by the courts 

 are many that are regarded as the gravest evils of expert 

 testimony. With doors wide open to incompetent persons, 

 very [slight pecuniary advantage, and still more frequently the 

 incidental benefit attributed to notoriety and advertisement 

 would cause them to seek entrance. As a result differences of 

 opinion may be anticipated where knowledge is wanting as a 

 basis. Then, too, the number of such experts in any case will 

 be greater. The cross-examination absolutely necessary to 

 test such evidence must be exhaustive and tedious. Trials are 

 prolonged. The expense of the administration of justice is 

 increased without furthering its ends, and withal often with 

 incidental discredit not only of the testimony of experts, but 

 in a measure of the whole judicial procedure which is 

 responsible for them ; and the jury are often left in such a state 

 of mental confusion that the evidence can only be weighed by 

 counting the experts. Now the rule should tend toward a 

 greater strictness in regard to the qualifications of experts, 

 since the progress of science tends towards a greater degree of 

 specialisation in study, and consequently to more minute and 

 extended evidence on the whole, with greater restrictions 

 on the range of best evidence of any particular expert. If 

 science stood still, or if forensic science was confined at all 

 ti.Tiesto the same old ground, everything would be settled, but 

 as it is, the new points at issue continually arising make new 

 demands upon experts, which there may be few at first 

 qualified to meet. The introduction of advanced scientific 

 expert testimony is then hardly a matter of option. It is 

 forced upon the courts by the fact that science is just as 

 ready in the hands of the unscrupulous and dishonest to perpe- 

 trate the most flagrant wrongs as to aid in their detection, and 

 that there is no advance in science that is not as accessible to 

 the enemies of society as well as to society itself. 



" But another, even more prolific source of complaint than 

 laxity of rule in the admission of experts, lies in the anomalous 



NO. 1242, VOL, 48] 



position of the expert in many respects, and under the best 

 ciicumstances. lie is legally a witness, an ordinary witness, 

 but practically with extraoidinary functions and one loaded 

 with extraordinary respcnsibilitics, and one might add, fre- 

 quently loaded with extraordinary, and even absurd, expectations. 

 As a witness he is sub] cenaed by the same form, obliged to 

 respond under the same penalties, to take the same oath ; is 

 subject to the same rules and restrictions, and the same treatment 

 in court. He has no higher claim upon the State, or upon the 

 parties for his time or his private professional knowledge, which 

 constitutes his livelihood. He receives, in most cases, to be 

 sure, from the party calling him, a fee agreed upon between 

 them, and certainly out of proportion to those of other witnesses, 

 even if it is not professional in magnitude. He assists the side 

 on which he is called in working up its case. He suggests the 

 cross-examination of witnesses. He thus exhibits the character 

 of a very willing w itness, of a well-paid witness, combined with 

 a great deal of the advocate. Now he cannot be held responsi- 

 ble fur this position, but the system of jurisprudence, which 

 not simply permits it, which has not simply taken him, but 

 has forced him in, and which, apparently cognizant of all, 

 seems only able to originate complaints, rather than to provide 

 a different character for him ; for there seems, indeed, in 

 many of the adverse criiicisms of experts, to be only a 

 confession of weakness, rather than a disposition earnestly 

 to consder the whole question with a view to the radical 

 remedy of the evils. The human nature of the judge is 

 recognised and provided against. Every safeguard is thrown 

 around him to protect him from bias, or possible suspicion of 

 bias, which would be almost as bud. The jury is selected so as 

 to be free from bias, and is protected .as well. Other witnesses 

 are not expected to take the part the scientific expert is almost 

 compelled to take. In fact, if deliberately planned, there could 

 hardly be a network of conditions devised, calculated to produce 

 so many of the evils of scientific expert testimony complained 

 of, or to cloud this testimony of highest intrinsic value, having 

 the highest degree of certainty, and in a field altogether its 

 own." 



" But in regard to the charge of bias," Prof. Himes after- 

 wards goes on to say, "it may be admitted that the scientific 

 expert may at times be biased, but that is only admitting that 

 he is made of the same clay as other men. The bias, if not 

 produced by the call, would certainly not be more of a rellectioB 

 on his character than upon the system of jurisprudence whicb 

 renders a call based upon bias not only possible, but almort 

 necessary, and which provides no other method for the intro- 

 duction of scientific testimony. But bias may be in nowise 

 incidental to the call. It may be a purely scientific bias, due to 

 some peculiar view or theory. No kind of training will fortify 

 a man against bias at all points. In his laboratory, in conduct- 

 ing his investigations, the scientific expert may keep himself 

 free from bias. The judge upon the bench is free from bias by 

 habit, ra her than by conscious effort. But even the judgCi 

 placed in some novel position of great responsibility, which this 

 judicial habit does not fit exactly might lapse into a bias. . . . 



"The criticism due to differences of opinion frequently ex- 

 hibited by scientific experts can hardly be regarded as a serioM 

 matter by a profession characterised by differences of opinions 

 on all conceivable points ; the only settled opinions known to it 

 being those of the court of last resort, which even claims the 

 privilege occasionally of reversing itself. Differences of opinion 

 among scientific experts .nre often doubtless due to differences in 

 scientific character, resulting from the loose rule of admission. 

 But there may still be honest differences between experts of 

 highest character. I think such, however, it will be found, are | 

 rarely in regard to well-established facts, but oftener in regard 

 to probable inferences from facts, whilst entire agreement would 

 be marvellous in matters of theory and speculation. Courts and 

 attorneys do notdiscriminate sufficiently between well-established 

 scientific facts and scientific theories. Some of the most recent 

 and far-reaching decisions of our highest tribunals have a basis 

 of theory rather than of fact." 



This leads to a point which we have always insi-ted upon, 

 namely, that a scientific expert shoyld i>ot be called and sub- 

 sidised by a particular side, but should be appointed by the 

 judge or jury. To quote Pjof. Ilimes : — 



" Many of the most objectionable features of the expert witness 

 originate in the mode of his entrance into court, and it is an 

 allowable question, whether any modification could be made in 

 the calling of the witness. Among the reports one judge ex- 



