Polygraph test

“ Specter. What is your opinion as to its level of reliability in measuring patterns of deception in a normal person?
Mr. Herndon. Well, the polygraph, of course, measures certain physiological responses which have to be interpreted. It must be clearly understood that the physiological responses that are portrayed on a polygraph chart can often be caused by things other than deception, such as fear, anxiety, nervousness, dislike, and many other of these emotions.
A polygraph examiner has to be extremely skilled and conservative in his estimation as to whether or not it is deception. ”

“ Mr. Herndon. The examination would be completely inconclusive or invalid in view of the fact that a psychotic individual is divorced from reality, and the tracings on his polygrams could not be logically interpreted.
Mr. Specter. Then is it necessary that a person be in touch with reality and understand the nature of the questions and answers in order for a polygraph examination to have any validity?
Mr. Herndon. Yes, it is.
Mr. Specter. Did you have occasion to conduct a polygraph examination on Jack Ruby? ”

“ In that regard it is expected the person would probably either hedge or deceive,582 and, therefore, the examiner can usually have an indication of whether or not this person will respond to a deception based on the examinee’s response to that question.
Mr. Specter. Mr. Herndon, what is the policy of the Federal Bureau of Investigation on the use of the polygraph examination?
Mr. Herndon. The FBI uses the polygraph technique purely as an investigative aid, in very carefully selected cases. ”

“ Jack Ruby wants to have this polygraph taken in accordance with his prior request to the Commission on June 7, 1964, and the commitment given by the Commission through the Chief Justice that such a polygraph examination would be given. ”

“ A microscopical examination of paper documents, such as wills, notes, checks, etc., as to whether or not they have been mutilated or forged, is certainly the most reliable test, and by far the easiest and simplest method of determining the authenticity or spuriousness of a document. ”

“ This is considered a control question, and its response is greater than his response to the previous relevant question which I had related.
Mr. Specter. Would there be any difference in psychological reactions, Mr. Herndon, on a pattern of deception which the subject considered insignificant as opposed to a pattern of deception which the subject considered significant?
Mr. Herndon. Generally the concept of the polygraph technique is that we are attempting to find out what a man’s physiological responses will be in any area where he is attempting to deceive. ”

“ Mr. Specter. Is there any overall limitation on the amount of time that a person can appropriately take a polygraph examination?
Mr. Herndon. Yes, there is a limitation. Certainly if a person is interviewed with polygraph at great length, in due time he is bound to become desensitized to the technique. In other words, the pressure on his arm and the technique itself becomes less valid as the increase in time proceeds.
Mr. Specter. Did Mr. Ruby ever become desensitized to the technique?
Mr. Herndon. I believe in the last series of the first session, which I believe is series 4, Mr. ”

“ Mr. Ruby. Yes, I was very voluntary.
Mr. Specter. We deliberately didn’t go into some areas, suffice it to say, for certain purposes. But this is the question we’re concerned with at the moment, and we would like an answer substantively, in addition to testing his truthfulness. It comes to a head when we try to formulate the questions for the polygraph, because we really have to get the underlying facts, and then we can point our efforts to see whether he’s telling the truth according to the indicators from the examination.
Mr. Fowler. ”

“ Mr. Herndon. This is a polygraph chair. The reason it is so constructed, we want to take advantage of these high arms [indicating arms on the polygraph chair] so that we can get a better tracing, and very frankly, Mr. Ruby, I want to give you as best an examination as I can. So, it’s going to take a little time and I want you to relax as best you can. I realize you might be a little nervous, and I will certainly take that into consideration. Let me just briefly, Mr. Ruby, tell you about the polygraph examination and what we’re going to do today. ”

“ If the test results are to be used by any other person than the examiner, this is absolutely essential. Any other standard of completeness opens the door to carelessness and inaccuracy. In nearly all the tests, except that of naming sixty words, the examiner will find it possible by the liberal use of abbreviations to record practically the entire response verbatim. ”

“ It must be borne in mind that the scoring is not a purely mechanical affair. Instead, the judgment of the examiner must come into play with every record made. If the scoring is delayed, there is not only the danger of forgetting a response, but the judgment is likely to be influenced by the subject’s responses to succeeding questions. Our special record booklet contains wide margins, so that extended notes and observations regarding the child’s responses and behavior can be recorded as the test proceeds. ”

“ Mr. Herndon. You see, this 100 percent American type question doesn’t necessarily lend itself to polygraph examination.
Mr. Specter. I agree with your conclusion, but what we’re trying to do now is to cover all of the important substantive questions which I think we have. After Mr. Ruby tells me that he is satisfied with what we have covered, I propose to ask the same question of Mr. Fowler and Mr. Alexander and also Mr. Tonahill, so that we will have covered the subject matter. We will do our utmost to be all-inclusive here, so that whatever effect the polygraph can gage as to Mr. ”

“ No positive rule can be laid down for the classification of their peculiarities excepting the manner of accuracy with which the simulation appearing in them is done. Each case of disputed writing must be examined by itself, and while there are certain process steps to be followed which experience suggests as facilitating the analysis, yet the examiner must wholly depend upon what is seen in the disputed signature that is, or is not, found in the admittedly genuine writing of the person whose signature is questioned, and the comparison of the one with the other. ”

“ It may be necessary to make these tests over a period of years, and the tests themselves may and probably will require frequent revision and amendment as it is found in the course of their application that some of them are unnecessary and others inadequate. If it is found that any of the tests so applied is readily fulfilled by every subject examined, the effort is made to increase the difficulty of the test, until it has reached a stage where the perfect performance of all its requirements is barely within the reach of the ablest and most competent of all the engineers under examination. ”

“ As a rule enough of each response should be recorded to enable one to score it at any time later. The great advantage of the Record Booklet is that it permits this. Only the most expert examiner should limit his record to pluses and minuses.
5. The examination should be thorough. It should include at least one year in which there is no failure and at least one year in which there is no success. When lack of time necessitates an abbreviation of the examination, this should be done by using only the starred tests rather than by shortening the range of the examination. ”

“ Kuhlmann requires pen and passes the child only when two trials out of three are successful. But these authors locate the test at 5 years. Our results show that nearly three fourths of 4-year-olds succeed with pencil in one out of three trials if the scoring is liberal. It makes a great deal of difference whether pen or pencil is used, and whether two successes are required or only one. No better illustration could be given of the fact that without thoroughgoing standardization of procedure and scoring the best mental test may be misleading as to the degree of intelligence it indicates. ”

“ Once, however, tests have been applied to the supposititious thousand expert engineers, and the performance of each of them in each test has been given its proper place in the scale, and an average struck, there has come into existence a preliminary standard; which, however, before being offered for general use in the testing of engineering students and others, must first be tried out by experimental application on as many individuals and groups as are available, and their performance with reference to the standard checked up by all other means available. ”

“ Those of average intelligence more frequently try to supply the proper symbol for each different digit in order as they appear in the test without going through the entire test with each symbol separately. The method of the candidate in doing the work should not, however, be allowed to influence the rating obtained on the test, except as one method may produce a higher score than another. ”

“ Seeking to resolve the question of obviousness with more uniformity and consistency, the Court of Appeals for the Federal Circuit has employed an approach referred to by the parties as the “teaching, suggestion, or motivation” test (TSM test) , under which a patent claim is only proved obvious if “some motivation or suggestion to combine the prior art teachings” can be found in the prior art, the nature of the problem, or the knowledge of a person having ordinary skill in the art. ”

“ A further test has to be applied by each investigator for himself. When we have ascertained, as far as possible, on what evidence our knowledge of an alleged fact rests, we have to consider the inherent probability of the allegation. Is the statement about it in accordance with the general workings of human nature, or with the particular working of the nature of the persons to whom the action in question is ascribed? Father Gerard, for instance, lavishly employs this test. ”

“ Applying this rule, illustration 341 is a tented arch, referenced to a whorl. Figures 342 and 343 are loops, referenced to whorls. Figure 344 is a plain arch, referenced to a loop.
No set rule can possibly be devised to enable a classifier to know with certainty where to draw the line when it is doubtful which classification should be given such a print. Individual judgment is the only standard. The test is: if the pattern, in the opinion of the classifier, is rolled to only a normal width, it should be classified as it appears. ”

“ Is that correct?"
"Yes."
"Sources of error can exist in handwriting analysis, can they not? There are a lot of judgment calls just like there is in most professions, isn't that correct?"
"Yes."
"So we really have no evidence that handwriting analysis is infallible. In fact, there are document examiners that are honest enough not to claim that."
"Well, they must be graphologists. We are on a different basis and it cannot be carried over to what we are doing."
Trenchant then named a well known document examiner and asked if Avery knew of him.
"Of course."
"Is he a graphologist?" ”

“ First of all, Ruby has obviously been extensively interviewed by law enforcement officers and by the Commission and other people, and there has been a considerable length of time lapse since the time that the instant offense occurred of him shooting Oswald. These factors of length of time and considerable previous interrogation would tend to detract or negate any specific or definite conclusion that could be rendered with regard to the polygraph examination.
The fact that there were other personnel in the room would tend to negate a valid polygraph technique. ”

“ We recount the Policy's most salient features, leaving aside complexities not relevant to the case at hand. To gain admission to one of Boston's three examination schools, a student must take a standardized test. Based on a mathematical formula that purports to predict academic performance, school hierarchs combine each applicant's test score with his or her grade point average, derive a composite score, rank all applicants accordingly, and proceed to assign individuals to the applicant pool for the examination school (s) in which they have indicated an interest. ”

“ If with the Stanford pictures we require three satisfactory responses out of four, the test belongs at the 12-year level, but the standard of two correct out of four can be met a year or two earlier.
Even after we have agreed upon a given series of pictures, the formula for giving the test, and upon the requisite number of passes, there remains still the question as to the proper degree of liberality in deciding what constitutes interpretation. There is no single point in mental development where the “ability to interpret pictures” sweeps in with a rush. ”

“ While it is a fact that the microscope and a knowledge of its uses is of the greatest importance in ascertaining the character of the signatures, when the question of their being forged or genuine is the object of the examination, it does not follow that because a person is learned in the use of the microscope in other fields of research that he is therefore qualified to become an expert in handwriting. ”

“ When Diana named her source of information and held up the book of a prominent document examiner, his reply was, "That person must come from a different viewpoint that I do."
"It appears that what you refer to as graphologists, in your profession, are much more thorough in their analysis of handwriting and printing than you are. The author of this book makes a point of insisting on original, authenticated standards and doing several different types of measurements. The idea being that when they decide a document's author, it is based on several different tests. ”