DETECTING THE CRIMINALS.

Evening Star, Issue 25677, 28 December 1945, Page 4

DETECTING THE CRIMINALS.

Early iu the preparations for the Nuremberg trial a suggestion was put forward by a certain American representative that the accused Nazi leaders should be subjected to a so-called “liedetector ” to test their guilt or innocence. This ingenious suggestion does not appear to have received any support from the other three Powers participating in the conduct of the trial, and it is probable that nothing more will bo heard of it. It is more than likely that the Allied prosecutors will believe that the guilt of tbo accused has been proved to the hilt by the evidence deduced without it being necessary to have recourse to any scientific means of determining the question. At all events, iu this case, the issue of guilt or innocence is largely a matter of ideologies rather than wrongdoing in strict legal terms. By their beliefs and actions the Nazi leaders put themselves above and beyond the law as it is generally understood in democratic countries. Their crime was against civilisation and the world as a whole. The facts are clear, and no amount of testing, either by drugs or electrical instruments, is likely to determine whether or not the accused knew that they were doing wrong, which is probably the most that could be expected from such methods. Much interest has been shown in America in. recent years in lie detection by scientific means for the purpose of assisting courts in deciding the guilt of accused persons, but there is no record of British courts having admitted evidence of this nature. There is probably a good deal of scientific justification for the belief that a guilty person’s- statements when under the influence of a disarming drug, or his reactions as recorded by instruments, will assist in establishing, the case against him. but the British sense of justice for many years yet is likely to look mistrustfully on such methods. Generally speaking, an accused person is not expected to assist in his own conviction if he denies his guilt, and if the prosecution is unable to prove the case he must he given the benefit of the doubt. Apart from these principles, which have been accepted for so long in British courts, there is still a good deal of doubt about the efficacy of the systems of. lie detection so far developed. Investigations are by no means recent. Native* races have for centuries used crude methods which have some scientific basis. In some countries the truth of an accused person’s statements when testifying m his defence has been tested by the dryness or dampness of the palms of his hands. In China it was once the practice to compel a subject to chew rice while he was being cross-examined and then to produce the. rice for inspection. Since lying the secretion of the salivary juices, if the rice was produced in a dry state the guilt of the suspect was accepted as proved. (Recent developments have been more complicated. American scientists have developed the use of drugs as so-called “truth sera.” Under a form of narcosis produced by such drugs a person may be induced to answer questions without' using the controlling or inhibiting influence of the higher centres of the brain. In other words, the person is unable to survey. critically his replies, and presumably, is most likely to tell-the truth. . Electrical instruments which record changes in pulse .rate, respiration, and blood pressure have also been ‘used to check: the correctness of a persons’ answers to questions. These are systems which sound plausible, but it may still be questioned whether they take into full consideration the complexities of the human brain and its capacity for adjustment to abnormal conditions. Perhaps the doubtful value of such practices was most forcibly pointed by the bright cable message published some months ago of the experience °f the use of _ a lie detector in an American asylum for the insane. A subject to whom the apparatus had been fitted was asked it he was Napoleon. His answer was no, but the detector showed he was lying*