Orne, M. T. Implications of laboratory research for the detection of deception. Polygraph, 1972, 2, 169-199.

IMPLICATIONS OF LABORATORY RESEARCH FOR THE DETECTION OF DECEPTION

By

Martin T. Orne, M.D., Ph.D.

Director, Unit for Experimental Psychiatry Institute of the Pennsylvania Hospital and Professor of Psychiatry, University of Pennsylvania

Introduction

A considerable degree of misunderstanding has existed between the psychophysiologist interested in the mechanisms involved in the detection of deception and the practitioner who must daily make difficult decisions in the field of lie detection. The differences in training and orientation between the two would, in themselves, be a sufficient cause for miscommunication; however, even more serious is the tendency of each to view the work of the other with skepticism -- or even distrust. As many others have pointed out, the application of psychophysiology to the detection of deception has been developed mainly by individuals whose basic skills were those of interrogation, and while the technique is often referred to as a scientific aid in investigative work, it usually has been taught either by apprenticeship with an established expert or through attendance at relatively brief seminars and courses. Despite the increasing concern with upgrading training standards and a growing awareness of the need for basic psychophysiological research in the application of the polygraph to the detection of deception, the effectiveness of the technique still depends to an overwhelming degree on the skill and experience of the individual polygraph examiner carrying out the procedure -- a point of view


A condensed version of this paper was presented at the annual meeting of the American Polygraph Association, Chicago, August, 1972.

The substantive research reported herein was supported in part by the Institute for Experimental Psychiatry. I would like to express my appreciation to my colleagues in the Unit for Experimental Psychiatry, Mary R. Cook, Frederick J. Evans, Charles Graham, Emily C. Orne, David A. Paskewitz, and Harvey D. Cohen for their helpful comments and suggestions in the preparation of this manuscript. I am particularly grateful to Mr. John E. Reid for his detailed critical comments.


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certainly shared by the members of this organization. Considering this state of affairs, it is particularly gratifying for me to again be asked to address this organization. I hope that some of my comments may help clarify and explain the differences in points of view between psychophysiologists and the practitioners of lie detection and make it somewhat easier for both to learn from each other.

When polygraphers explain the technique there is a tendency to emphasize the physiological nature of the recordings and point to the objective charts as evidence that the procedure is based on scientific principles. Research scientists, on the other hand, have tended to dismiss these claims, partly on the basis of trivial but technically correct objections to the somewhat primitive techniques of physiological recordings used. A more telling criticism, however, is the paucity of scientific evidence concerning the validity and reliability of the technique. The researcher emphasizes that merely recording physiological data, even with the best of instruments, does not make lie detection "scientific." He tends to demand clear, unequivocal evidence about how often and under what circumstances such data permit the accurate detection of deception. For reasons to be discussed later, such evidence has simply not been available.

In fairness, though, it should be pointed out that few researchers with the necessary scientific and psychophysiological sophistication have made serious efforts to evaluate the use of lie detection techniques in the field and, with a few notable exceptions, statements by scientists have tended to be based on very limited experience with the technique as well as strong prejudice against it. In the same vein, field polygraphers have tended to ignore and deprecate laboratory studies on the detection of deception. They correctly recognize that important differences exist between the suspect being interrogated about a crime and the volunteer laboratory subject taking part in a study, concluding -- all too often, inappropriately -- that little or nothing of importance can be learned from such research.

Lie Detection -- A Misnomer

It is, of course, recognized by field polygraphers and psychophysiologists alike that the physiological changes often observed to be associated with lying are no different in kind than those seen whenever an individual is exposed to a novel situation or suddenly experiences emotions such as fear, anger,

 

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elation, excitement, anguish, and so forth -- in other words, any form of emotional arousal.. Not only are the physiological changes as such unrelated to lying, but it is not even the act of lying per se which brings them about. This observation can readily be documented in laboratory experiments.

In one study (Gustafson & Orne, 1963) using a simple card test, subjects were asked to select a numbered card from among several and then to reply NO each time they were asked by tape recording whether they had selected a card with number 12, number 17, 14, 18, and so forth. The rate of detection under these circumstances, defined as an increased electrodermal response to a selected card, was hardly greater than chance. However, when the identical procedure was carried out with another group of subjects who had first listened to a short tape recording informing them that only intelligent and mature individuals had the kind of emotional control necessary to fool the lie detector -- implying that this procedure served as a test of their emotional stability -- they showed rates of detection far greater than chance. This and related evidence have led us to conclude that it is not lying but rather motivated deceptive intent which leads to recognizable augmented physiological responses.

A study by Kugelmass, Lieblich, and Bergman (1967) further documents this point, again using a card test with subjects motivated to deceive but now requiring them to answer YES each time a tape recording asked whether they had taken a particular card. Thus, if a subject had selected the number 15 and was asked, "Did you take the number 17?" he would be required to answer YES; if asked, "Did you take the number 12?" he would be required to say YES, and so on, in each instance lying. However, when the subject was asked, "Did you take the number 15?" -- which he had selected -- he would be telling the truth. Under these circumstances, subjects motivated to deceive could readily be identified at far greater than chance levels by their augmented physiological response while truthfully answering that they had selected their particular card. It is clearly not lying which produces an increased physiological response in this situation since the subject is required to lie every time except when responding to his card but the physiological response produced is less than that observed when he is telling the truth about his selected card. (Reid and Inbau [1966] suggest an analogous procedure for field use.) This

 

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demonstrates that both in the laboratory and in the field it is the deceptive intent rather than the act of lying which yields an augmented physiological response.

The term "lie detector" tends to be misleading in yet another sense. Since there is no unique physiological pattern associated with lying and individuals differ widely in their physiological responsivity, no one can identify a given response as a lie or even as indicating deception without comparing it to the same individual's physiological response to other stimuli. In other words, the technique of lie detection depends upon developing adequate control questions with which to compare those questions where one seeks to evaluate deceptive intent. As every field examiner knows, the adequacy of a "polygraph test" depends upon the appropriate form of questions Though there are technical differences between various approaches, all procedures seek to determine how the individual responds physiologically to both trivial and arousing questions when it is known whether he is truthful in order to permit inference to be drawn about his response to the items about which he is being examined. Ideally, the examiner develops control questions which, to an innocent suspect, would be at least as emotionally arousing as the critical questions, whereas to a guilty individual the critical questions should be far more arousing than these control questions. Consequently, with a guilty individual the critical questions will elicit a greater physiological response than the control questions but this would not occur with an innocent individual. The real skill in the use of the polygraph to detect deception lies not so much in obtaining an adequate physiological record but rather in the examiner's ability to develop appropriate comparison questions which permit a valid interpretation of the suspect's physiological response to crucial questions.

All lie detection tests are therefore preceded by a pretest interview which serves a number of important functions. It makes possible the developing of appropriate control questions, permits the polygrapher to evaluate the suspect, obtain necessary background information and establish the kind of relationship which facilitates the test by trying to maintain a level of concern likely to yield an optimal physiological record. Inevitably, the pretest must also serve to convince the suspect of the effectiveness of the polygraph.

While the importance of the pretest interview is recognized among field examiners, its crucial significance is hardly ever

 

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stressed in a court of law. Indeed, while examiners keep both their charts and questions, few keep tape recordings of the pretest interview. Yet control questions are formulated and their appropriateness evaluated during this interview which, by its very nature, plays a major role in determining how the suspect will respond physiologically during the actual test. Thus Reid and Inbau (1966) have often emphasized the danger of interrogation during the pretest interview and how such a procedure inappropriately carried out might inadvertently serve to sensitize an innocent suspect to relevant questions.

The Relationship Between the Laboratory Experiment and the Field Situation

Once it is recognized that the experimental subject's motivation to deceive plays a crucial role in his detectibility, it becomes self-evident that no laboratory situation is likely to produce as intense a desire to deceive the interrogator as is characteristic of the lie detection situation in the field. Since the consequences of detection in the laboratory can hardly approach those involved in actual interrogation, there is some justification in the practitioner's claim that the likelihood of detection in an experiment will tend to be greatly diminished when compared with most lawful situations. Why then do laboratory research at all? Would it not be best, as has been advocated by some, to answer all questions that need to be answered by lie detection in real life situations, using data from field interrogations? After all, these are the situations about which we wish to make inference. While such an approach would be desirable, unfortunately many pertinent questions cannot be answered economically with data obtained during actual interrogation, and some of the most important issues (to be discussed below) can hardly be dealt with at all.

Basic Questions Which Require Clarification

The first question which is typically asked about the detection of deception concerns its validity. How effective is the procedure in detecting lying? How frequently does the examiner conclude that a suspect is telling the truth when he is actually guilty (false negative), and how frequently does an examiner erroneously conclude that an innocent individual is in fact guilty (false positive)? This "simple" question turns out to be extremely difficult to resolve.

 

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In order to clarify it, it would be essential to have absolutely reliable information about the truthfulness of a suspect during a lie detector test, and then it would be necessary to determine whether an expert polygrapher is capable of recognizing deception based exclusively upon his pretest interview with the suspect and a subsequent polygraph test. However, neither ground truth nor truly independent polygraph evaluations are available.

There are a number of ways in which these issues have been addressed. The most typical estimate of validity is based upon a retrospective study of polygraph examinations. The incidence of examiners' reporting deception, no deception, and inconclusives is recorded, and these conclusions are then examined to see in which instances evidence to the contrary has been developed. Thus, if an examiner has carried out 1000 tests and in only two instances did he later learn that his decision was challenged by information subsequently developed, he might conclude that the procedure is better than 99% accurate. Such an approach assumes that the decision of the examiner is correct unless proven to be wrong subsequently, an assumption which is hardly justified since, in many instances, subsequent data never come to the attention of the examiner and, for that matter, the truth may never emerge.

A somewhat more sophisticated procedure would involve comparing the judgment of the polygraph examiner with the ultimate disposition regarding a given set of cases. Thus, one would determine how frequently a suspect who is called guilty by the examiner is subsequently convicted of the crime concerning which he was tested; conversely, what the likelihood would be of a suspect who is considered innocent by the polygraph examiner actually being released. While such an approach appears objective, it too cannot yield a fully satisfactory answer about the effectiveness of the polygraph in ascertaining truth.

In police settings, for example, the polygraph is widely used as a means of establishing presumptive innocence. Usually, when a suspect successfully passes the polygraph tests this means he is eliminated from serious consideration. Granting that the polygraph has reasonable validity, such a procedure makes excellent sense in husbanding the investigative resources of our law enforcement agencies. On the other hand, from the point of view of establishing the validity

 

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of the instrument, it is catastrophic. If a suspect actually is guilty but manages to successfully pass the polygraph examination, the likelihood that his guilt will subsequently be correctly identified is greatly diminished since the effort to turn up additional evidence is largely abandoned.

The situation is only slightly better in instances where the examiner finds evidence of deception. True, there are clear instances where individuals confess following such an examination and the confession is corroborated by other information developed subsequently. Nonetheless, there is always a marked effect of a suspect's failing to pass a polygraph examination on the course of the subsequent investigation even if an individual is, in fact, innocent. Being judged deceptive on a polygraph test might even increase the likelihood of his being found guilty, since law enforcement officials might well tend to dig harder for information corroborating the suspect's guilt insofar as their own convictions about his guilt had become strengthened by the outcome of the test. To the extent that such increased zeal could have an effect on the ultimate disposition of the case, regardless of the actual guilt or innocence of the individual, it would tend to distort the conclusions one might reach about the polygraph.

The only way ultimate disposition could meaningfully be used as a criterion by which to evaluate the validity of the polygraph examination would be to prevent the investigating officers from obtaining any information about the outcome of the polygraph examination. While of interest theoretically, such a procedure simply could not be instituted in actual practice.

One final point needs to be considered. Not only does the finding of the polygraph examination tend to affect the subsequent course of the investigation, but the amount of information available concerning the suspect's guilt at the time of the examination may also affect the results of the polygraph test. Since the polygraph is an investigative tool, the examiner is given whatever information is developed in the course of the examination prior to interrogating the suspect. Such a procedure is appropriate if one wishes to maximize the accuracy of the overall polygraph test procedure; however, it is not appropriate if one hopes to evaluate the polygraph test's unique contribution to the detection of deception. The problem is somewhat analogous to the use of

 

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x-ray findings in clinical medicine. The referring physician provides a brief, relevant history which is available to the roentgenologist when he is reading the films. Clinical information of this kind helps tremendously in focusing his attention on the relevant aspects of the films and crystallizing the likely diagnostic alternatives about which he is being asked to comment. From the point of view of obtaining the best available judgment about an x-ray film, such a procedure is highly desirable; however, it is less than appropriate if one seeks to determine whether it is possible to make a correct judgment based on the film itself. To answer such a question would require that crucial information be withheld from the roentgenologist at the time the film is being read. Similarly, if one hopes to determine the effectiveness of the polygraph as a means of detecting deception, it becomes important to control the kind of collateral information available to the examiner. It is difficult to avoid having one's judgment influenced by reliable information about a case, especially in situations where the data upon which the judgment is to be based is somewhat ambiguous. However, the problem is considerably more complex in the case of the polygraph examination than in the evaluation of x-ray diagnoses. Thus the x-ray technician's beliefs about the likely diagnosis can have little, if any, effect on the nature of the actual x-ray film that is obtained; on the other hand, the polygraph test is not a cut-and-dried procedure and it is hard to believe that even a well-trained and experienced polygraph examiner's private biases about a suspect's potential guilt or innocence might not exert some significant influence on the manner in which he conducts his pretest interview and the examination itself. It must be emphasized that in a polygraph examination the suspect's physiological responses to questions depend in good part upon the nature of the pretest interview, his beliefs about how the interrogator views him, and on how the questions themselves are asked. Further, the interpretation of his responses to relevant questions depends upon the nature and quality of the control questions. Consequently, a polygraph examiner's biases not only could affect the manner in which he reads his charts but might also cause the suspect to respond differentially, resulting in charts which are, in fact, objectively different. Therefore, any attempt to determine the validity of the polygraph as a means of ascertaining truth in field situations would require the examiner to be ignorant of any information bearing on the suspect's guilt or innocence

 

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that had already been developed.* Since such a limitation would tend to interfere with the most effective use of the technique, it too is unlikely to be imposed for the sake of validating data in actual field situations.

What I have tried to make clear here is that in a real-life context the outcome of the polygraph examination is likely to be influenced by evidence developed by others concerning a suspect's guilt or innocence and, similarly, the outcome is also likely to be influenced by the polygraph examiner's own prior suspicions about the suspect's guilt or innocence. For the purpose of establishing scientific validity, however, it is absolutely essential that the results of the polygraph examination be totally independent of the results of other aspects of the investigation, a condition that in practice cannot be met objectively in a real-life situation.

In response to this, highly experienced polygraph examiners have invariably been able to point to cases where at the beginning of the examination they were convinced of a suspect's guilt but found as the session progressed that the charts corroborated the suspect's asserted innocence. Their findings, distinctly at variance with their own strongly held convictions as well as those of their colleagues, were subsequently borne out as more evidence was developed and someone else was shown to be responsible for the crime in question. Similarly, they will point to cases where an individual apparently above suspicion, who was tested only to satisfy the requirement that everyone be examined, proved to be deceptive and ultimately guilty. Certainly such experiences are compelling evidence of the integrity of the examiners as well as of the polygraph's effectiveness in those particular instances.

It is my personal conviction that in proper hands, appropriately used, the polygraph examination can be a very powerful technique to ascertain truthfulness. Unfortunately, in real-life situations it is not possible to translate this belief into a meaningful, quantitative estimate of validity.


* It should be emphasized that similar and closely related problems exist in the interpretation of a great many apparently objective procedures such as psychological tests and, of course, psychiatric examinations.

 

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Of necessity, society demands more of us than our impression that the polygraph can be a useful procedure and, for the reasons outlined above, the problem of establishing independent criteria of truth and the outcome of the polygraph examination is incredibly difficult. This does not mean that one should cease trying to evaluate experience in the field.

Two Studies Bearing on the Validity of the Polygraph

Bersh (1969) developed an estimate of an individual's actual guilt or innocence by having three trained members of the Judge Advocate's staff go over all available information concerning an individual. This included information which would not be admissible in a court martial proceeding but had bearing upon the determination of an individual's actual guilt. The judgments made by these three individuals were then compared with the polygrapher's decision based on the polygraph examination which was carried out during the actual investigation. This retrospective study represents the kind of follow-up investigation that is possible though extremely difficult to carry out.

The findings are of considerable interest. Thus, when all three lawyers reviewing the case agreed about the guilt or innocence of an individual, their judgment agreed with the polygrapher's original judgment 92.4% of the time; when only two of the three lawyers agreed, the agreement dropped to 74.67%. The interpretation of these findings is somewhat difficult, however, and illustrates the problems outlined earlier. Thus, one could argue that in situations where ground truth was reliably determined, a very high degree of consensus existed between the polygrapher's initial decision and truth, but when there was some question about ground truth, leading the reviewing lawyers to disagree, the relationship between the polygrapher's judgment and the estimate of truth was greatly diminished. Indeed, it is entirely possible that in many instances the polygrapher was, in fact, correct.

On the other hand, it can equally well be argued that in those instances where all three attorneys agreed it, is likely that a great deal of evidence had already been developed at the time of the original polygraph test and that, the same evidence which influenced the attorneys' judgments also had a profound effect on how the polygrapher treated the suspect, how the suspect responded, and the

 

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judgment the polygrapher subsequently reached. In other words, this study suffers from all of the problems of the non-independence of the polygraph examination from data about an individual's guilt or innocence that had been collected prior to the test as well as the non-independence of the course of the investigation following the polygraph examination from the decision reached by the polygrapher at that time.

In many ways the most interesting study is that by Horvath and Reid (1971) who used 40 records (20 each guilty and innocent) of moderate difficulty where truth was presumably known and the polygraph decisions were verified by independent evidence. The polygraph records and questions were given to several experienced examiners who were able to identify deceptive records with a high degree of accuracy, ranging from 85 to 97.5%. Since the examiners' statements were based exclusively on the physiological responses to specific questions, many of the objections raised previously do not seem to apply. Nonetheless, even here caution is necessary in interpreting the findings. The cases selected were originally correctly identified by the field examiners. One could argue that this identification depended upon an appropriate pretest which in turn led to recognizable physiological responses. Thus, the fact that other examiners can correctly identify guilt or innocence in these verified instances of the original examiners' correct judgments merely proves that individuals trained within the same laboratory tradition can identify those aspects which they view as indicative of deception in physiological data with considerable reliability. A true validity study would have to ask about the effectiveness of identifying deception in situations where ground truth is independently established and where the total procedure, including the pretest examination, is evaluated. If one selects cases where the pretest procedure led to a correct identification of guilt or innocence, one is inevitably stacking the cards for the technique and focusing on reliability which is only one of the requisites of validity.

Despite their limitations, both of these studies represent major advances and hopefully will be followed by additional efforts in this direction. Nonetheless, it seems clear that we need to be very careful about validity statements based on field data. Unfortunately, the typical data which are cited are largely based on the unverified experiences of individual field examiners. Thus there is a tendency for polygraph examiners to believe that their decision was accurate

 

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unless subsequent information proves it to be wrong -- in other words, when an individual is considered innocent and no subsequent proof of guilt emerges or when an individual is considered deceptive and he is not hired or dismissed from his job. However, it is by no means improbable that such groups will include instances where an individual who is judged to be innocent is, in fact guilty but no proof of his guilt is ever developed; further, it could well include individuals who were considered deceptive and therefore excluded from a position they were applying for but who were, in fact, innocent. If such instances exist, it is unlikely that they would come to the attention of the polygraph examiner.

Above and beyond these issues there are further difficulties in interpreting the statistical observations obtained in the field. Consider the hypothetical example of an office in which 100 people are employed and a theft occurs. All employees claim to be innocent and they are tested on the polygraph. The guiltlessness of each of the 100 individuals is corroborated by the test. Subsequently one individual is identified from among this group by some other means and it is established that he, and he alone, was responsible for the theft and that none of his coworkers had any knowledge or connection with it. Would the polygraph expert therefore be justified in claiming that this experience shows the polygraph was 99% accurate?

An assertion such as this is, of course, ludicrous since from the point of view of an outside observer it represents a failure for the polygraph. When the situation is seen through the eyes of the polygrapher, however, he, in fact, has tested 100 individuals and in each instance was forced to reach a judgment of deception or no deception, and this judgment was actually correct for 99 of the 100 individuals. The difference is that subjectively the polygrapher feels as though he must weigh the likelihood of guilt or innocence equally every time he examines a suspect; from his point of view the probability of guilt or innocence of each individual case is 50%. If the situation were really such that there were as many guilty as innocent individuals and he correctly identified 99 out of 100, the claim of 99% accuracy based on such data would be justified. The only reason why his view is incorrect is that the group contained only one guilty individual and the polygraph expert presumably knew that the likelihood of innocence was far greater than the likelihood of guilt.

 

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In other words, the probability of finding the guilty person was 1 in 100, and in order to demonstrate that the technique is effective it is necessary to show that it does better than chance. Obviously, this in not true in this instance. It seems clear that in order to avoid reaching conclusions which seem naive on the one hand, or unfairly penalizing the polygraph expert on the other, studies must be designed in a way to include a sufficient number of guilty individuals to permit intelligent assessments of the separate probability for false positives and false negatives. Thus, the correct observation based on this hypothetical example would have been that in 99 instances there were no false positives; however, in the only instance when a false negative could have occurred, it did occur. Consequently there were 0% false positives and 100% false negatives (though the latter figure is based on only one case.)

The Importance of Conservative Criteria

This problem is not unique to lie detection as it can be met in both psychiatry and medicine. Indeed, evaluating the effectiveness of a given treatment shares many of the difficulties we have discussed above. The physician's belief in the effectiveness of a given treatment will affect how he and the family treat the patient and what the patient himself does, which may in turn have a profound influence on the outcome. These ancillary effects, known collectively as the placebo component, are quite independent of the therapeutic effect itself. Invariably, as new treatments are developed, there is a tendency to report significant results, arising in part from the doctor's enthusiasm and in part from the natural tendency to assume that patients who do not return for treatment are improved. These problems were sufficiently serious to force medicine to develop some very rigid runes in evaluating results.

An example of such rules is the five-year cure rate used to evaluate various cancer treatments. The concept of a five- and ten-year cure rate has subsequently become basic in all efforts to evaluate cancer treatment. For instance, surgery for cancer of the breast is performed and if the woman is alive five years later she is considered as a five-year cure; even if she is dying of cancer she is still considered a five-year cure as long as she is alive at the end of five years. Similarly, if she is alive ten years later, it would be considered a ten-year cure. The crucial point here, however, revolves around the fact that if the

 

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operation is successful, and she is alive and well with no evidence of cancer at the end of four years, but is hit by a car while crossing the street and dies and therefore is then not alive at the end of five years, she must still be listed as a failure of surgery. This is done simply because she is not alive, regardless of cause. You might say this is obvious nonsense because the woman who was hit by the oar and had no evidence of cancer was, in fact, more successfully treated than the woman who was dying of cancer but still alive at five years -- and you would be correct.

The inherent difficulty here, of course, is that it is not possible to determine whether the woman who died as a result of the auto accident at four years might not also have died of cancer during the fifth year. If this seems like a trivial objection and you decide to accept the four years, what do you then do with the woman who dies of an auto accident after two years, etc.? In other words, it is best to develop rigid, and of necessity conservative, criteria. This makes possible a meaningful comparison of different treatment methods since the chance errors even themselves out while the possibility of bias affecting the results is reduced. In establishing criteria of these kinds one is forced to make estimates which are generally highly conservative in order to limit oneself to hard evidence but, in the final analysis, such data are far more compelling.

In presenting the case for lie detection to the public in general and the legal profession in particular, hard data is essential -- and conservatism is likely to be far more convincing than undocumented enthusiasm. Recently a number of well-known polygraph experts during court testimony were asked first how many polygraph tests they had administered and, after indicating their extensive experience, they were asked, "How many inaccurate polygraph tests do you know of by your personal knowledge?" Typically the answer was none or at best one or two, a very small number indeed when compared to the total number of tests administered.

This is a very impressive answer and perhaps, in the position of an adversary proceeding, many here would also have been tempted to elicit testimonials of this kind. On the other hand, care should be exercised since such statements tend to sound too good to be true. Further questioning would also reveal that follow-up evidence is not systematically collected in the usual course of a polygrapher's professional duties. Indeed, you yourself might try a little

 

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experiment of your own. Speak to some of your friends in police departments who are detectives and who interrogate many suspects -- not using the polygraph but just interrogating -- until they form a conviction about the individual's guilt or innocence. Ask them how frequently their considered judgment after an extensive interrogation has been shown to be inaccurate. I suspect that you will find few detectives indeed who will report more than a very small number of instances where their considered judgment was proven wrong. This is not only because errors of this kind fail to occur but more due to the selective nature of memory when dealing with subjective data. One wonders if perhaps it is the intuitive awareness of these difficulties which makes an individual seem more credible when he is able to recall instances of being wrong!

Advantages of Laboratory

Although the laboratory setting has its own problems in contrast to the field situation, it is nonetheless possible to create scenarios in the laboratory where subjects become highly involved and are then required to take polygraph examinations. The test can be administered by a different investigator who is not privy to the particular experiences the subject has had during the earlier parts of the experiment. Consequently there is little difficulty in creating subjects who are known to be truly innocent concerning the matters about which they will be interrogated and to create others who are truly guilty in the sense that they will have committed some kind of mock crime or been given access to some secret information. It is also possible to create yet a third group of individuals who have varying degrees of information about a crime but are innocent. These would be analogous to bystanders who, for one reason or another, have access to knowledge about a crime and might be subject to interrogation.

Again, in contrast to the field situation, it is relatively easy in an experiment to make certain that the examiner does not have access to any information about the actual guilt or innocence of the subject. Further, since the interrogation of all the subjects concerns essentially the same crime, it is possible to standardize it and carry out objective analyses on the data. Under these conditions we can establish truly independent criteria of guilt and innocence in relation to detection by the polygraph. Further, we have control over the proportion of guilty and innocent

 

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subjects, making it possible to obtain meaningful data about the incidence of false negatives as well as false positives. Such information is particularly difficult to obtain in the field because of the relatively low percentage of guilty individuals among the total number who are tested.

Most important, however, in the laboratory it is feasible to have perfectly designed control questions without the need to painfully develop them during a pretest interview. For example, in a card test the numbers on the cards which the subject did not select serve as appropriate control questions. The availability of almost perfectly matched comparison questions may in large part compensate for the inability to create the intense motivational factors inevitably present in the extra-laboratory context.

It should be emphasized, however, that the primary virtue of laboratory studies is not to provide a measure of validity; rather it is to help us understand the mechanisms which affect the likelihood of detection. It becomes possible to systematically vary such factors as the subject's motivation to deceive by varying the consequences of being detected, to vary the amount of involvement of the subject with the experiment, to vary the subject's beliefs about the effectiveness of the polygraph and his ability to deceive the interrogator, and so on. As mentioned earlier, in a series of studies we have been able to demonstrate that the motivation to deceive greatly increases the probability of detection. We have also shown that if the subject is given evidence that he can successfully defeat the polygraph examination he will be far less likely to be detected on subsequent polygraph tests. In other words, it has been possible to examine some of the psychological factors which affect the probability of detection.

One can ask questions about the effectiveness of different common, real-life patterns of polygraph questioning, comparing, for example, the peak-of-tension approach with the relevant-irrelevant method. Here, as always, it is crucial that the laboratory situation appropriately reflects the salient aspects of the field situation. For example, in our effort to compare peak-of-tension with relevant and irrelevant questions, Gustafson and Orne (1964) initially observed that in an experiment the relevant-irrelevant technique was far more effective than peak-of-tension. The procedure employed was to ask subjects to select one card

 

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from several numbered cards. In one instance all the numbers were then asked randomly as an analog to the relevant-irrelevant method; in the other, they were asked sequentially such as 34, 35, 36, as an analog to peak-of-tension procedures.

We noted that subjects attempting to deceive were able to do so successfully on some of the peak-of-tension trials by choosing to give false responses to an incorrect number in the laboratory context. This procedure, as any of you gentlemen would recognize, would, of course, not be effective in a real-life context since any competent examiner would merely ask the suspect to explain his response and thereby undercut this rather simple countermeasure. Accordingly, the experimental procedure was modified. Subjects were again told to select one numbered card from several. They were also informed that among these cards were some which were blank, as was actually the case. Their task this time, however, was to convince the investigator that they had in fact drawn a blank card. This was explained as analogous to a real-life interrogation where they would need to document their innocence and at the same time not appear guilty of another crime. With this relatively minor change of procedure we observed that the peak-of-tension technique became extremely effective, perhaps even slightly more effective than the relevant-irrelevant procedure.

The evolution of this experiment is described in order to show the care with which research must be designed in order to adequately reflect the life situation. A failure to do so may lead to erroneous conclusions. We cannot afford to give up the insights that can be gained from laboratory research because it is possible to misinterpret laboratory results, but we can and must evaluate procedures carefully lest inappropriate inference be drawn.

Thus far I have carefully avoided mentioning any statistics concerning the rate of detection obtained in laboratory contexts. This has been deliberate because such data are essentially meaningless unless care is taken to understand the details of the experimental procedures employed. In contrast to the field, almost all laboratory research uses a procedure analogous to the card test. The subject selects one of several numbered cards and he is then asked about all of the cards in order to see whether his response to the card he selected can be correctly identified. As in an actual interrogation, the first question

 

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is always a "dummy" since the initial response of an individual is routinely augmented. Usually, but not necessarily, on the basis of the electrodermal response a determination is then made concerning which physiological response was the greatest. If the response to the selected card was, in fact, the greatest, then the subject would be considered detected; if another response was equal or greater, he would not be considered detected. While there are many variations on this procedure, most laboratory studies use quite objective but highly arbitrary means of analysis in order to establish whether or not detection took place. Consequently the researcher loses the very important clues which the polygrapher has available from asking the suspect to explain his response. He also tends to deal with individuals at a much lower level of arousal. On the other hand, he has the major advantage of perfectly matched comparison questions -- a luxury not usually available in real life. On the other hand, this alone may make up for the much lower motivation to deceive found under laboratory circumstances.

Many laboratory studies involve questions about several different items. Thus, an individual may be required to deceive about a number of different items of information If, for example, the subject was given six different sets of questions, the probability of correct detection could range from 0 to 6. A detection rate might be based on the percent of times the individual is correctly detected. Thus, if he is detected three times correctly, one might say the rate of detection is 50%. Note that in this instance the detection rate is within the individual subject. In terms of discriminating guilty subjects from innocent subjects, however, the rate of detection takes on different aspects. If each question had four items, the likelihood of detection by chance each time would be 25%. A group of innocent subjects would tend to have an average detection rate of 1.5 items, or one-fourth of the total number of questions, though an occasional innocent subject might by chance have two, or very occasionally even three, correct detections. The likelihood of an individual with three detections being innocent would be extremely low --1.6%. Thus, if an individual was detected four out of six times, one would be almost certain he was in the guilty group, even though the overall rate of detection of information was only 66 2/3%. This principle of using multiple questions in order to make discrimination between guilty and innocent individuals more reliable was employed particularly successfully by Lykken (1959) who

 

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constructed a series of questions based on individualized information and was able to obtain accurate discrimination between individuals who had guilty knowledge and those who did not in approximately 90% of the cases. In one experiment, using a refinement of this procedure with 25 questions, he was able to correctly detect individuals with guilty knowledge 100% of the time.

Caution is required in reading the experimental literature since the rate of detection in some studies is meant to apply to the number of times a correct response is identified; in other studies, to the number of times the correct individual is identified. Different studies use widely differing social interactions as well as differing in the number of sets of questions asked. Not surprisingly, therefore, detection rates ranging from random to 100% have been reported under different circumstances. In the abstract they have little meaning beyond documenting that under some specifiable circumstances a highly reliable level of detection can be achieved. However, in attempting to extrapolate from the laboratory to the field, it must be kept in mind that the polygrapher lacks the many advantages inherent in perfect control questions. In theory, the peak-of-tension procedure has precisely these virtues, but as Reid and Inbau (1966) have outlined and as Barland (1972) has extensively discussed, the ideal situation is rarely available in real life.

While the absolute figures on detection rates in the laboratory are of very limited significance, one instance when they become extremely useful is in clarifying the effects of different psychological mechanisms on the probability of detection. Probably the most important finding from all laboratory research is the overwhelming importance of psychological factors in determining whether an individual will or will not be detectible in the lie detection situation. Perhaps the strongest disagreement scientists would have with polygraphers is in the extent to which psychological factors rather than physiological factors are seen as crucial in making the detection of deception possible. Thus, in testimony before courts and in presenting the lie detection interview to the suspect about to be interrogated, the polygrapher tends to speak about the physiological response to lying. As has been discussed earlier, there is no evidence whatsoever to indicate any specific physiological response associated with lying; on the contrary, whether or not an individual

 

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can be correctly detected in any given situation tends to be a function of his motivation, his concern about the consequences of being found out, his past experience in lie detection situations, the manner in which he is questioned, the extent to which he can be persuaded that the instrument is effective, and so on. Factors such as these are, of course, psychological though they will determine whether or not there is an augmented physiological response to the critical stimulus about which the suspect is trying to deceive.

There may well be some important virtues in presenting the technique of lie detection to a suspect as if augmented physiological response was an invariant, unavoidable concomitant of deception. Such an assertion, while useful in increasing the probability of the suspect's detection, is not, in fact, true. Indeed it is used in the field because the suspect's belief in the lie detector is important in maximizing the likelihood of a physiological response while lying. The obverse is equally true, namely that under some circumstances the likelihood of an augmented physiological response while lying is greatly reduced. The factors which determine whether this is the case are also almost overwhelmingly psychological as opposed to physiological. Thus neither drugs, fatigue, or even anxiety tend to have very pronounced effects in reducing detectibility provided the individual remains responsive, concerned about the outcome of the test, and shares the belief in the likelihood of deception being detected by the test.

On the Validity of Polygraph Data

As I have tried to point out, the information is simply not available to permit a reliable estimate of the validity of the polygraph in life situations. Extrapolating from the laboratory, however, one can say that when a subject is very concerned about the probability of detection, he does become more detectible. Assuming that the psychological conditions of the polygraph test are appropriately met and that the polygraph examiner is truly competent in carrying out an effective pretest interview and designing appropriate comparison questions, it is likely that the detection rates will exceed those observed in the laboratory. On the other hand, it is by no means clear how frequently the average examiner in the field meets the high standards of competence and objectivity which characterize some of the outstanding

 

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practitioners, nor how carefully the optimal circumstances for an examination are created. Nonetheless, I would certainly agree that a competent interrogator, trained in the use of the polygraph, attempting to evaluate deception with the aid of the polygraph test will be significantly more effective than without it. Further, I believe that in appropriate hands the reliability of the polygraph is far greater than what one could expect from accounts of eyewitnesses who briefly observe a stressful and arousing event. Certainly it would be more reliable than other available techniques of ascertaining truth such as psychiatric evaluations or more esoteric procedures such as the use of hypnosis or "truth serum."

Countermeasures

While it is difficult and risky to extrapolate a validity estimate for the field from laboratory data, other questions can be asked with greater assurance in the laboratory. One of these concerns the circumstances under which the polygraph becomes less reliable. Here one is concerned not with the absolute detection rates, but rather with the effect of various interventions on relative detection rates. It is no longer necessary to extrapolate from the detection rate in the laboratory to that in the field; as long as the laboratory reflects the same mechanism observed in a field situation, the estimates of relative effects of various countermeasures are meaningful. Unfortunately, very few systematic studies are available. The early work of Kubis (1962) suggested that yoga-like control was not effective in some instances but various muscular-techniques and imagery were reasonably effective. Our own data clearly show that a subject who strives to escape detection and is provided with experience in a polygraph test which convinces him that he is able to fool the machine will become very significantly less detectible on subsequent tests. (Conversely, if it is demonstrated to him that he can be detected, he will become more detectible.) This observation has important field implications which will be discussed later.

Aside from some anecdotal reports, little is known about the effects of specific drugs on detection or the effects of systematic training procedures using conditioning, repeated retests, feedback techniques, and similar potentially meaningful approaches.

 

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The Assumptions of the Polygraph Test

One tends to describe any test as though it matters little when, where, how and by whom it is administered; however, even in the case of highly objective tests it is implicitly assumed that certain conditions are met for the procedure to be valid. Consider, for example, the taking of blood pressure in a doctor's office: for the readings to be valid it is necessary that the patient be cooperative and reasonably relaxed. Readings can be distorted by an unduly high level of anxiety as well as a wide range of drugs. Further, one must assume that the individual who is taking the patient's blood pressure carries out the procedure correctly. The findings will validly reflect the general state of the patient's vascular system -- as opposed to its momentary response -- only if the conditions under which they were obtained meet these assumptions. Similarly, in order to obtain a valid test of an individual's intelligence it is essential that the subject be cooperative, motivated, not unduly frightened, have had a reasonable amount of rest and be free from the deleterious influence of drugs. The findings from an individually administered intelligence test are further predicated on the assumption that reasonable rapport exist between subject and examiner, and that the latter follow a carefully standardized procedure in administering the examination. An I.Q. determination is a meaningful, objective measure of abilities only to the extent that all of these assumptions are met, though one inevitably obtains a score regardless of the circumstances under which the test was administered.

The assumptions upon which a valid administration of a particular test depends are usually well known within the field but are rarely spelled out. Not infrequently, violations of these assumptions fail to be recognized because the factors that distort the results are relatively subtle, even though the circumstances under which the test has been administered may lead to inappropriate comparisons. For example, intelligence tests administered to subjects of a different cultural background with different sets of values and no experience in taking tests often result in gross underestimates of ability. Incorrect conclusions can be drawn from such data if the investigator fails to recognize that the changed circumstances prevent the test from validly reflecting the subject's abilities.

 

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It would seem worthwhile to make explicit the underlying assumptions which guide the behavior of the good polygraph examiner and the circumstances under which the overwhelming bulk of his experience is obtained.

All polygraph examiners strive to maintain a professional relationship with the suspects they are about to examine. The nature of this relationship is patterned after that between the interrogator and suspect though there may not be any formal interrogation. The fact that polygraph examiners are drawn from the ranks of interrogators helps assure this aspect of the relationship to the individual about to be tested. Though styles of interrogators vary widely, all maintain an arm's length relationship with the interrogatee. Even when the style is one of extreme friendliness and solicitousness it is still clear that the interrogator is in control of the situation, "calls the shots," and makes the judgment.

Polygraph examiners vary in the manner of the pretest interview but these interviews are inevitably designed to accomplish three major goals: (1) to subtly but effectively convince the suspect about the effectiveness of the polygraph, (2) to develop appropriate comparison questions, and (3) to make certain the suspect understands the questions he is to be asked and what the examiner means by an honest answer. The pretest interview also serves to evaluate the suspect, to gauge and appropriately modify his level of anxiety, and to subtly establish the examiner's competence in the field.

Considerable emphasis is placed by all examiners on the need for professionalism and a professional relationship with suspects. Inevitably such a relationship serves to increase the examiner's prestige and effectively communicates his high degree of competence. Finally, much of the examiner's behavior is designed to emphasize the importance of the polygraph test to the suspect, specifically to make him acutely aware of the consequences of being adjudicated as non-deceptive or deceptive. While most modern workers emphasize the objective aspects of the examination and behave as though their role was merely that of an expert technician who views himself as a scientific tool, it is always clear to the suspect that the examiner's judgments will have a material effect on his future life. It is, of course, also assumed that the suspect is well rested, and that his level of concern

 

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while high is not incapacitating.

Though various schools differ about the most effective kind of comparison questions and how they should be asked, all polygraph examiners agree that such questions are essential for a meaningful interpretation of the charts. Further, it is assumed that the examiner asks relevant questions with no more emphasis than that used in asking comparison questions, that the examiner avoids "springing" any questions on the suspect, especially relevant ones, and that appropriate rapport is maintained throughout the test.

It is assumed that appropriate physiological sensors are appropriately applied, that the equipment is in good working order, and the examiner appropriately marks his records. Though different examiners vary in their emphasis on different aspects of the physiological records, it is assumed that some rational and reproducible method of evaluating the charts is utilized. Although the number of charts that are obtained and the role of interrogation before and between the charts are not fully agreed upon, all examiners concur in the need to verify the judgment of deception by using several relevant and several comparison questions and by obtaining more than one chart.

Finally, there is consensus that repeating polygraph examinations a large number of times will tend to affect the nature of the charts obtained, though it is not established what kind of changes will occur and at what point they may serve to invalidate the test.

In considering the validity of polygraph examinations, it is necessary that these conditions of the polygraph examination have been reasonably approximated. It will be clear, of course, that the examiners themselves vary widely in experience, competence, social experience and interrogative ability. Factors such as these can hardly help affect the likelihood of detection. Furthermore, the crucial role of the pretest interview has not received adequate attention, especially when polygraph findings are discussed in court. While in truly expert hands the pretest interview is carried out in a manner which assures optimal conditions for the polygraph test, one can readily conceive of situations where inappropriate handling of the pretest situation can produce charts leading to false positives or false negatives. For this reason it seems vital that, in addition to maintaining records of the actual questions asked and the polygraph charts, tape

 

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recordings of the pretest interviews be kept. Without such information anyone seeking to interpret the objective charts must assume that the pretest interview was appropriately carried out but is unable to judge the adequacy of the procedure itself. If the polygraph were to be considered, for example, in courts of law, recordings of this kind should certainly be made available as one of the bases for cross examination.

The Friendly Polygrapher

Recently a series of attempts have been made to introduce polygraph evidence in courts of law as the basis for corroborating a defendant's assertion of innocence. These cases all shared an important feature: they involved a polygraph test administered by a polygraph examiner at the behest of the defense attorney. In several instances these examiners have been highly respected and competent in their field. Obviously, it is desirable in such cases to have an examiner whose reputation and character are above reproach for him to be effective were the polygraph evidence to be admissible in court.

While the examiner himself may have had vast experience and great competence, assuring thereby that the test itself meets most major assumptions, the very situation in which such tests are given in fact tends to violate some of the most important aspects of the situation which makes polygraph tests work.

Whereas the usual polygraph examination is carried out in a situation where the polygrapher is at arm's length -- in the employ of a law enforcement agency, a potential (or actual) employer or in some similar relationship, where his decision would inevitably have a direct effect on a suspect's future --the context in which the friendly polygrapher carries out his test is inevitably different. In the latter case the suspect realizes that his attorney has employed the polygraph examiner to help in the preparation of his defense. For the innocent person this may matter relatively little; however, for the guilty individual it alters the situation considerably. The guilty individual when tested by a friendly polygrapher knows that the results of the test if he is found deceptive will not be used against him. The only kind of findings which his attorney would utilize are ones where his innocence is being corroborated by the polygraph. As a consequence, the client's fears about being detected are

 

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greatly reduced. As we have been able to show in the laboratory, and as is acknowledged by all polygraph experts, a suspect's fear of detection is the major factor in assuring his augmented physiological response while lying. It is precisely this aspect of the situation which is most dramatically altered when the polygraph is employed by the defendant's attorney. The respect and perhaps even deference accorded to the client by the polygraph examiner will tend to convince the client that the polygrapher is really attempting to help his cause and thereby make him less afraid and less detectible, even if he is guilty.

In addition to this basic problem, there is an almost inevitable difference in the manner in which the polygraph examiner actually treats his client. Whereas interrogators commonly address suspects by their first name and act aloof, the polygrapher in the employ of the defense attorney will tend to be more cordial and more pleasant. He will have a far greater tendency to address the client formally by his last name and will tend to show subtle signs of respect far more readily than when he is examining a suspect at the behest of the authorities or an employer.

Typically, the pretest information given to the polygrapher by the defense attorney will emphasize all the evidence substantiating his client's innocence, and the attorney will appeal for his help to establish for the authorities a fact which he presumably already knows -- that his client is innocent. Whatever effects a bias to believe in a suspect's innocence may have on the subsequent polygraph examination will work in favor of the examiner's perception that the client is innocent.

It should be emphasized that these difficulties will tend to distort the results of the polygraph examination even with an extremely competent and highly experienced examiner who is genuinely trying his best to make an honest evaluation of an individual's truthfulness.* Most troubling about this situation is the fact that the polygraph examiner will, of course, interpret the charts against a background of his vast experience with individuals who have been tested


* Obviously the far greater likelihood for conscious or unconscious bias to distort the manner in which the test is administered and how it is interpreted when examiners other than the most outstanding are employed hardly requires comment.

 

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in an arm's length situation, usually failing to recognize the potentially serious distortions of the situation introduced by his altered relationship to the client. It goes without saying that, even under these adverse circumstances, competent polygraph examiners have frequently identified clients as deceptive. This speaks to the competence of the examiners and to their integrity. It does not, however, permit any inference to be drawn about the validity of the test in those instances where the client appears innocent. Information would have to be sought in these specific contexts and no such data has ever been developed. It would certainly be inappropriate to conclude that any validity estimates based on other experience with the polygraph are relevant to the friendly polygrapher context. Whatever problems exist in estimating the validity of the polygraph in more usual situations are compounded in this context.

From a purely legal viewpoint, it is, of course, clear that if polygraph data were used only when a client is considered non-deceptive and otherwise suppressed, the meaning of the polygraph test would inevitably be diminished, even if its validity were not seriously impaired in this situation.

It would seem much to the best interest of polygraph examiners in general to avoid permitting themselves to be used in the friendly polygrapher situation. For the reasons outlined above, their findings are inevitably less likely to be valid; further, since only data supporting the innocence of a client would ever be introduced, the respectability of the polygraph procedure would in the long run be diminished, especially as instances of its inaccuracy under these circumstances come to the attention of the public. This seems particularly germane since these difficulties can readily be avoided. It would merely be necessary for professional polygraph examiners to decide that they agree not to administer tests and subsequently testify concerning them unless the findings were stipulated in advance by both defense and prosecution. While such a situation would, of course, place a tremendous responsibility on the examiner and raise complex legal and moral issues, it would prevent a serious potential misuse of the technique which could in the long run only serve to damage rather than enhance its acceptance. On the other hand, by refraining from carrying out tests except under circumstances where the existence of real consequences for the suspect is assured and unfavorable reports cannot simply be excluded, examiners would take a major step toward the ultimate acceptability of the technique.

 

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Needed Future Research

I have tried to indicate how laboratory research on the detection of deception can help clarify some of the mechanisms which appear to be operative in the field situation. Certainly many of the conclusions which can be drawn from laboratory studies can and should be explored in field situations. However, some questions can be addressed adequately only in experimental contexts and many of these are as important to the basic sciences as they are to the polygraph examiner. Despite the intrinsic interest of the phenomenon and the tremendous growth of the field of psychophysiology, there has been remarkably little systematic research specifically directed at the basic issues underlying the detection of deception. Recently we have tried to summarize the literature and outline some of the important psychophysiological issues (Orne, Thackray, & Paskewitz, 1972). It seems clear, however, that a great many important questions remain to be clarified, and surprisingly many of these can be appropriately addressed at the research laboratory.

The technology of lie detection is based almost exclusively upon three physiological measures: the pneumograph, the "cardio" and the electrodermal response, and utilizes techniques of measurement which have not been significantly altered since the 1920s. While the pneumatic system of recording respiration and the cardio channel are probably adequate for purposes of the test,* the electrodermal response is recorded by relatively primitive but reasonably effective systems (though the electrodes can and should be improved even for the field situation). On the other hand, the use of other physiological sensors has received little attention in field situations. Of particular promise are various kinds of plethysmographs to measure peripheral vascular responsivity more directly. The potential use of EEG recordings has received little attention, nor has there been much effort to utilize muscle tension which, under some circumstances, may prove to be particularly interesting. Similarly, the interpretation of charts has not been standardized nor, with the exception of the work of Baxter (1962), has


* Though, of course, for more detailed analysis by computer it is necessary to make analog tape recordings of the signals and alternate forms of recording then become necessary, such techniques are neither required nor desirable for most field applications.

 

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much attention been paid to its quantification. All these issues are of interest; however, the importance of an improved physiological technology in terms of sensors and parameters of analysis can easily be overemphasized. The most important questions about the detection of deception remain psychological.

The overriding effects of some psychological factors have been reliably identified; however, many others remain to be clarified. Questions such as the effect of multiple testing on detection, an eminently practical problem if the technique is to become more widely used, have never been systematically explored. The extent to which the examiner's beliefs about a suspect's guilt or innocence can actually serve to distort the physiological record obtained urgently needs clarification. The ease with which subtle changes in the manner in which questions are asked during a test may distort the obtained chart needs to be determined, and the extent to which simple psychological maneuvers may serve to increase the suspect's detectibility requires investigation. The feedback technique suggested by Golden (1971) is an example of a promising procedure which can and should receive careful research attention.

In a similar vein, all of the problems generally subsumed under the question of countermeasures may ultimately serve to clarify the nature of the mechanisms upon which the detection of deception depends. Thus, the extent to which specific drugs, hypnosis, training in self-hypnosis, the manipulation of cognitive expectancies, the changes and consequences attached to detection, specific feedback training, extensive experience with and knowledge about the polygraph and its use, and so on, affect detection remains to be established. Finally, the importance of cultural differences, both on the physiological responsivity of the individual and the significance associated with lying, is bound to play an important role in an individual's detectibility. Kugelmass and Lieblich (1968) have reported such differences in the modality of the electrodermal response but no information exists on whether individuals who fail to respond in that modality respond normally in others. Certainly the work of Lacey, Bateman and VanLehn (1953) on autonomic specificity would suggest that this might well be the case. Similarly, the effect of psychopathology on detectibility is almost totally unexplored beyond. anecdotal reports that psychopaths and psychotic individuals tend to yield uninterpretable charts.

 

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Hopefully future work will begin to fill in the broad gaps in our knowledge. As our scientific understanding of the mechanisms upon which the field use of the polygraph rests is increased, it is likely that the research scientist will become progressively more able to contribute meaningfully to the appropriate application of the technique. Of equal importance will be the added knowledge to the science of psychophysiology which can be developed by careful study of the practice of field examiners in their day-to-day work. As is often the case, the intuitive clinician develops and uses techniques, often without the full ability to explain or clarify their nature but nonetheless effectively, long before these procedures are fully understood. and quantified by the research scientist. There is little doubt that future work will show some inaccuracies in some of the cherished beliefs of polygraph. examiners; on the other hand, it is even more certain that many of the procedures developed from years of experience and careful observation will form the basis for significant contributions toward an understanding of the complex relationship between mental processes and physiological responses. One would hope that as field examiners and research scientists begin to fully appreciate each other's strengths and weaknesses, the likelihood of each contributing to the understanding of the other will progressively increase to the benefit of both.

REFERENCES

Barland, G. H. An experimental study of field techniques in lie detection. Unpublished Masters Thesis, University of Utah, 1972.

Backster, C. Zone comparison technique: Standardized polygraph notepack. New York: Author, 1962.

Bersh, P. A validation study of polygraph examiner judgments. Journal of Applied Psychology, 1969, 53, 399-403.

Golden, R. I.. Audio GSR bio-feedback in polygraph examinations. Paper presented at the meeting of the American Polygraph Association, Atlanta, August, 1971.

Gustafson, L. A., & Orne, M. T. Effects of heightened motivation on the detection of deception. Journal of Applied Psychology, 1963, 47, 408-411.

 

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Gustafson, L. A., & Orne, M. T. The effects of task and method of stimulus presentation on the detection of deception. Journal of Applied Psychology, 1964, 48, 383-387.

Horvath, F. S., & Reid, J. E. The reliability of polygraph examiner diagnosis of truth and deception. Journal of Criminal Law, Criminology and Police Science, 1971, 62, 276-281.

Kubis, J. F. Studies in lie detection: Computer feasibility considerations. Tech. Rep. 62-205, prepared for Air Force Systems Command, Contract No. AF 30(602)-2270, Project No. 5534, Fordham University, 1962.

Kugelmass, S., & Lieblich, I. Relation between ethnic origin and GSR reactivity in psychophysiological detection. Journal of Applied Psychology, 1968, 52, 158-162.

Kugelmass, S., Lieblich, I., & Bergman, Z. The role of "lying" in psychophysiological detection. Psychophysiology, 1967, 3, 312-315.

Lacey, J. I., Bateman, E. D. & VanLehn, R. Autonomic response specificity: An experimental study. Psychosomatic Medicine, 1953, 15, 8-21.

Lykken, D. T. The GSR in the detection of guilt. Journal of Applied Psychology, 1959, 43, 385-388.

Orne, M. T., Thackray, R. E., & Paskewitz, D. A. On the detection of deception - A model for the study of the physiological effects of psychological stimuli. In N. Greenfield & R. Sternbach (Eds.), Handbook of psychophysiology. New York: Holt, Rinehart & Winston, 1972. Pp. 743-785.

Reid, J. E., & Inbau, F. E. Truth and deception: The polygraph ("lie detector") technique. Baltimore: Williams & Wilkins, 1966.


The preceding paper is a reproduction of the following article (Orne, M. T. Implications of laboratory research for the detection of deception. Polygraph, 1972, 2, 169-199.). It is reproduced here with the kind permission of American Polygraph Associaton.