Perry, C. W., Orne, M. T., London, R. W., & Orne, E. C. Rethinking per se exclusions of hypnotically elicited recall as legal testimony. International Journal of Clinical and Experimental Hypnosis, 1996, 44, 66-81.



Concordia University, Montreal, Quebec, Canada


University of Pennsylvania, Philadelphia


London Associates International, Tustin, California


University of Pennsylvania, Philadelphia

Abstract: In 1993, Boggs argued for a rethinking of the per se exclusion of hypnotically elicited testimony. This article analyzes the Minnesota v. Mack (1980) case that initiated this exclusion and the two Illinois cases Boggs cites in favor of her position. The scientific data on the effect of hypnosis on memory do not support Boggs's position. Rather than providing reasons for rethinking this per se position, these data suggest that it should be retained.

More than 15 years ago, in State v. Mack (1980), the Minnesota State Supreme Court adopted a per se (i.e., automatic) exclusion of hypnotically elicited testimony: It ruled that a crime witness or victim who had been hypnotized following police instructions could not testify in court. However, it concluded that police could employ hypnosis with victims

Manuscript submitted April 26, 1995; final revision received August 22,1995.

1 The substantive research on which the views presented in this article are based was supported in part by NIMH Grants 19156 and 44193 to the second author's lab and by the Institute for Experimental Psychiatry Research Foundation. In addition, the first author was supported by Fonds pour la Formation de Chercheurs et l' Aide a la Recherche de Quebec (Principal Investigator: Jean-Roch Laurence, Ph.D.). These funding sources are acknowledged gratefully by their respective recipients.

2 The authors wish to thank four anonymous reviewers for their thoughtful and highly helpful critical comments. The final responsibility for the conclusions drawn in this article, however, is our own.

3 Requests for reprints should be addressed to Campbell Perry, Ph.D., Department of Psychology, Concordia University, Montreal, Quebec H3G 1M8, Canada or to Martin T. Orne, M.D., Ph.D., Institute for Experimental Psychiatry, 1955 Locust Street, Philadelphia, PA 19103.




and witnesses to construct an independent physical case against a defendant. The implicit argument appears to have been that if the prosecution could present such independent verification, there would be no need for the previously hypnotized witness to testify about what he or she had recalled in hypnosis. At the same time, the Mack court did not stipulate whether the fact that hypnosis had been employed to obtain evidence that was subsequently corroborated should be reported -- even though the witness would not be permitted to testify about how this additional recall was obtained. Rather, the court's concern was to establish that hypnosis had been employed "to investigate a crime rather than to create a witness" (p. 771).

Most American state supreme courts that have heard cases involving hypnosis have either adopted Mack or a variant of this decision, which is exemplified by the decision of the Pennsylvania State Supreme Court in Commonwealth v. Smoyer (1984). In this case, the court reaffirmed the per se exclusion of the Mack court. Unlike this earlier court, it permitted previously hypnotized witnesses to testify about their prehypnosis recall, provided that the prosecution could demonstrate that what they reported was a "true memory" of the prehypnosis period.

From the very beginning there was considerable concern, in some quarters, that both Mack and Smoyer placed far too strict limits on a prosecution, and some commentators felt that the courts themselves should determine the probative value of testimony based on hypnotic recall. More recently, Scheflin (1994) has maintained that such exclusions are "unjust, unfair and unnecessary" (p. 30) because in some cases, a traumatized crime victim, whose posttraumatic response might be assisted by hypnosis, is denied hypnosis as the result of a per se exclusion. Accordingly, he advocated admissibility of hypnotically refreshed recall on a case-by-case basis.

In addition, Boggs (1993) argued for reconsideration of the current per se exclusion of hypnotically elicited testimony that prevails in Illinois. She stated that the denial of hypnosis to crime victims who seek it as "a means of therapy”4 can result in "severe injustices" (p. 136). In

4 As a therapeutic procedure, hypnosis is considered by the relevant professional societies as an adjunctive procedure and not as a therapy in itself. That is, it can be employed to facilitate a clinician's preferred therapeutic method, be it psychoanalysis, behavior modification, insight therapy, Gestalt therapy, or whatever. Withdrawal of hypnosis does not deprive a clinician of his or her primary therapeutic strategy; it means only that an ancillary technique is withheld temporarily. Initially, a careful practitioner would seek to obtain a baseline of memory prior to any decision to employ hypnosis for additional enhancement of it. It may even transpire that this baseline procedure is sufficient to stimulate novel material to the extent of making a hypnosis procedure for memory enhancement purposes redundant. Boggs's (1993) confounding of a memory enhancement function with a therapeutic one, however, has tended, in the past, to be counterproductive -- particularly when the person performing the hypnosis is a police officer, with no formal credentials in medicine, psychiatry, clinical psychology, or one of the other mental health helping modalities.



addition, she maintained that "sufficient safeguards can be constructed to ensure credibility of the hypnotic process and reliability of previously hypnotized witnesses" (p.137).She expressed the view, also, that "hypnosis can be and is used as a key to unlock memories too painful to be discussed in the normal course of events" (p. 137). From this, she concluded that the existence of a per se exclusion prevents a crime victim or witness from testifying about his or her independent recollection of a set of events; this she found "illogical" and requiring reconsideration.

The present article was written in response to the points made by Boggs. It concerns itself with (a) the scientific data on the effects of hypnosis on memory, (b) the underlying rationale of the Mack court's per se exclusion, (c) an analysis of the two Illinois cases (People v. Zayas, 1989; Tardi v. Henry, 1991) on which Boggs's arguments for this reconsideration are based, (d) a discussion of the strengths and weaknesses of the Smoyer decision as an alternative basis for admitting the prehypnosis testimony of previously hypnotized crime witnesses, and (e) the merits and shortcomings of guidelines for the forensic use of hypnosis.


As can be seen from the foregoing, Boggs (1993) maintained that hypnosis can reliably reinstate inaccessible memories, perhaps even ones that appear to be repressed. She took the position, also, that the judicious use of "safeguards" (which she did not describe) will ensure that what is recalled in hypnosis is "truth." She acknowledged that hypnosis has its dangers in creating enhanced suggestibility, confabulation, deliberate fabrication, and increased confidence. She stated that these are justified concerns but that "any harm can be limited through the use of effective safeguards" (p. 137) and also a "totality of the circumstances" approach, which weighs all factors thought to be relevant to a case before a decision is made on the admissibility of hypnotically elicited recall. These views are crucial for her argument for reconsidered admissibility of hypnotically elicited testimony. The scientific data, however, do not support her views about hypnosis and memory.

As is well known, memory is not reproductive. It can become reconstructed as the result of the fresh inputs that constantly impinge on it and by such other factors as physical conditions at the time of encoding and the individual's beliefs, wishes, motives, and sets (Bartlett, 1932; Loftus, 1979). The introduction of hypnosis as a means of enhancing memory adds further problems, given that hypnosis can be seen as an invitation to indulge in make-believe and fantasy (Perry, 1992) or as a lowering of a response criterion (increased willingness to confidently report previously uncertain information; see Klatzky & Erdelyi, 1985).

Laboratory studies (see Orne, Soskis, Dinges, Orne, & Tonry, 1985, for a review) have indicated three main effects of hypnosis on memory. These are (a) hypnosis, usually, increases the productivity of recall, but



much of the novel material is error; (b) hypnosis increases confidence for both correct and incorrect information; and (c) these effects are independent of hypnotizability. Even individuals who are relatively unresponsive to a hypnotic procedure are likely to show increased productivity, error, and confidence when a hypnotic procecdure is employed to enhance recall. The magnitude of the effect, however, is somewhat less pronounced in low hypnotizables (Dinges et al., 1992; Nogrady, McConkey, & Perry, 1983).

These research findings present a very different picture to that described by Boggs. She cited an earlier Illinois decision (People v. Smrekar 1979), which stated that "medical authorities indicate that hypnosis has become established as a valuable tool in the hands of a skilled practitioner and can be used to restore the memory of experiences which have been repressed due to their unpleasant or painful nature" (Boggs, 1993, p. 136). She also stated that "it is clear that hypnosis has been accepted by the medical community as a valid technique for refreshing memory, especially those memories lost due to amnesia or a particularly traumatic event such as rape" (p. 138). Elsewhere, in an article that she wrote under a previous name (Clemens, 1991), she cited Arons (1967), a lay hypnotist, as a reliable scientific source for the belief that hypnosis enhances recall.

In fact, with regard to "medical authorities," the American Medical Association (AMA) (1958), in its report on the medical use of hypnosis, was silent about any presumed memory-enhancing properties of hypnosis -- that is, the hypnotic hypermnesia effect. In a subsequent statement of 1985, however, the AMA concluded that "recollections obtained during hypnosis can involve confabulations and pseudomemories and not only fail to be more accurate, but actually appear to be less reliable than nonhypnotic recall" (AMA, 1985, p. 1921).

Some critics (see, e.g., Reiser, 1985) have maintained that the data on memory and hypnosis have been collected in the benign context of the laboratory, where the level of stress permissible is negligible. On this view, such data do not generalize to the frequently affect-laden situation of a crime context. This viewpoint does not, however, take into account the fact that if these effects occur in benign circumstances, they are likely to exist, at least to an equal degree (if not more), in the more emotionally charged setting of a crime sequence.

As will be seen from what follows, these data indicate that hypnosis is a fallible technique that will elicit both accurate and inaccurate information. As such, if an investigation is at an impasse, hypnosis may be considered to provide potential clues or leads, but such information can be relevant to a court only if it has been established independently. Like sodium amytal, hypnosis is not a "truth serum."




The Mack (1980) court in Minnesota was the first state supreme court to impose a per se exclusion of hypnotically elicited testimony; it did not however, entirely rule out hypnosis as a source of testimony. It sought to resolve a difficulty in American law surrounding hypnosis that can be traced to an earlier decision. Harding v. State (1968), heard before the Maryland Court of Special Appeals, was a highly complex rape and attempted murder case, the events of which are difficult to disentangle. For present purposes, however, these events are tangential to the argument being advanced.

The Harding court ruled that hypnotically elicited testimony is admissible in court, leaving the jury the task of evaluating the effect of hypnosis on the witness's testimony. This raised the issue of whether juries can, in fact, treat hypnotically derived testimony in an identical way to any other form of evidence. In addition, neither the Minnesota nor the Maryland court made note of the fact that over a century ago, the law courts of France had been concerned with this very problem of the admissibility of hypnotic recall.

French experts on hypnosis of the 1880s concluded, eventually, that any novel information elicited in hypnosis might be (a) fact; (b) lie; (c) confabulation, that is, the confusion of fantasy as fact; or (d) a pseudomemory cued accidentally by the person performing the hypnosis. They concluded, additionally, that independent physical corroboration was the only way in which these four alternatives might be differentiated; they were aware, also, that at times, such a resolution between these four alternatives might not be possible (for a review, see Laurence & Perry, 1983, 1988).

The Harding decision held sway throughout the 1970s in American supreme courts (see Laurence & Perry, 1988; chap. 12). In two other cases (Emmett v. Ricketts/Creamer v. Hopper, 1975; United States v. Narciso and Perez, 1977), discussed by Diamond (1980), hypnotically elicited recall was considered by the respective courts as being more reliable than actual physical evidence. For instance, in Emmett v. Ricketts/Creamer v. Hopper (1975), which involved the murders of two Georgia pathologists married to each other, the evidence against Emmett and Creamer came entirely from hypnosis. In this case, nine people overall were charged, even though no physical evidence at the murder scene, including fingerprints, matched any of the arrestees. Additionally, four different juries heard this case, each unaware that there were major discrepancies in the testimony of the primary witness on each occasion that she testified. It was cases such as this one that led Diamond to conclude that witnesses who have been hypnotized should not be permitted to testify in court, on the grounds that they are incompetent to testify. State v. Mack (1980),



heard by the Minnesota State Supreme Court in the same year that Diamond's paper was published, came to an almost identical conclusion.


This case involved a woman who had met Mack in a bar in May 1978. Subsequently, he drove her on his motorcycle to a motel and checked into a room using his credit card. They continued drinking alcohol and had intercourse, during which she began to bleed from the vagina. Mack called for an ambulance and waited for it to arrive, after which he returned home. The ambulance driver testified that the patient appeared “quite drunk” and that during the drive to the hospital, she had volunteered that Mack was not at fault. At the hospital emergency department, she told an intern that she had been engaged in "sexual activity with fingers being placed in her vagina" (p. 766).

Another intern, who was on duty that night, told her that he thought that the wound could only have been caused by a sharp instrument, such as a knife, being inserted into her vagina.

Two days later, she telephoned the police to report an assault. A police officer interviewed the interns, the suspect, and the suspect's ex-wife. Some 6 weeks later, the police arranged for her to be hypnotized by a lay hypnotist. In hypnosis, this individual suggested that she would recall the events with Mack in the motel room, exactly as they had transpired, but on a television screen and without emotion. Her recall altered dramatically; she reported that on entering the motel room, Mack had ordered her to undress and to lie on the bed. She stated that “he told me to spread my legs. ...He pulled out this switchblade and told me he was going to kill me. ...He kept sticking this knife up me and I remember screaming and screaming” (p. 766).

The Mack court, in finding the defendant innocent, noted that there was no independent physical evidence to corroborate her hypnotically elicited recall. She had alleged repeated stabbings, but the medical record indicated only one vaginal lesion (which was consistent with her gynecological history). Further, there was no damage to the external genitalia, as would be expected in a case of repeated attempted stabbings inside the vagina. There were additional minor discrepancies in her testimony. For instance, she recalled for the first time in hypnosis that on the day of these events, she had lunched with her father at a restaurant and had ordered a pizza. This particular restaurant did not offer pizza on its menu. In addition, she described Mack' s motorcycle as a black Yamaha -- in fact, he drove a maroon Triumph.


The Mack court ruled that a previously hypnotized crime victim or witness could not testify in court but that any additional information



elicited in hypnosis could be used by police to construct a case against a defendant using independent physical corroboration. In such circumstances, there would be no need for the previously hypnotized witness to testify about his or her recollections in hypnosis. Further, it invoked Frye v. United States (1923) in ruling that "results of mechanical or scientific testing are not admissible unless the testing had developed or improved to the point where experts in the field widely share the view that the results are scientifically reliable as accurate" (p. 768). It went beyond Frye in one highly relevant respect.

The court maintained that merely to reassert Frye would be to permit the possibility of case-by-case adjudications of the admissibility of hypnotically elicited recall. This, in turn, raised the strong likelihood of lengthy voir dire hearings, with experts on both sides presenting submissions on whether a particular witness should be permitted to testify. Recognizing this problem, the Mack court stated that "a case-by-case decision on the admissibility question would be prohibitively expensive, and reveals the difficulty of getting experts qualified to testify about hypnosis as an investigative rather than a therapeutic tool" (p. 766).

An additional thrust of the Mack decision is in terms of permitting police to complete an investigation. The Mack ruling permitted police to follow any additional leads elicited in hypnosis, rather than have a court make decisions about uncorroborated recollections derived from hypnosis. It stated that

neither the person hypnotized nor the expert observer can distinguish between confabulation and accurate recall in any particular instance. After the hypnosis session, the hypnotically retrieved account differs in another way from ordinary human recall. ...Because the person hypnotized is subjectively convinced of the veracity of the "memory;" this recall is not susceptible to attack by cross-examination. (pp. 769-770)

As will later be seen, not all courts have subsequently agreed with the Mack court reasoning. Nevertheless, the decision was a thoughtful attempt to balance out police interests (in having access to a flawed technique that might be investigatively helpful on occasion), defendant interests (in not being subjected to a time- and money-consuming legal process on the basis of uncorroborated recall), and the court interest (in expediting a just decision at minimal unnecessary cost in judicial time and taxpayer money). The possibility that Smoyer may be a viable alternative to Mack is discussed later; before doing so, a discussion of Tardi v. Henry (1991) and People v. Zayas (1989) is relevant, given Boggs's citing of them as supporting her contention that reconsideration of the per se exclusion of hypnotically elicited recall is desirable.


Zayas (1989) involved the murder of three young men, all members of a Chicago street gang, in July 1983. Three of the four main prosecution



witnesses also had street gang credentials -- one testified that Zayas had admitted his involvement in the killings, and two others claimed to have seen him firing the gun. This was in contradiction to their earlier statements to the police that they had been in another room and had heard the shots. Hypnosis entered this case through Police Officer Michael Atkins's involvement in it. He testified that he had responded to a call to the murder scene but that he and his partner had not stopped their car when they saw that other units already had secured the street.

Subsequently, they observed a car containing four Hispanic males pull out in front of them, but there appeared to be nothing unusual about it. On returning to the murder scene, other officers informed them that a car similar to the one containing the four males might be involved. Atkins testified that after considering it, he thought the vehicle was a light-blue Plymouth Sebring, with a possible license plate number of XND 405.

Subsequently, the police officer was hypnotized by the psychiatrist Bennett Braun, M.D., and he recalled a different license plate number -- NXJ 402. The license plate number of the vehicle suspected was NXJ 240. The appellate court was not impressed with this apparent "near miss." It stated:

The fact that Dr. Braun was unaware of the license plate number is not determinative. The possibility that Dr. Braun suggested the actual license plate number is but one of the many problems this court finds with the process. Some of the other problems that the trial court did not address, and could not properly address, include whether Officer Atkins received some suggestion of the actual license plate number before hypnosis, for instance from a picture or a police report, the effect of the hypnosis on Officer Atkins regarding whether the State could properly cross-examine him, and the effect of the introduction of hypnotic evidence on the jury by bolstering jury confidence in Detective Atkins' testimony. Because it could not properly make these determinations, this court finds that the trial court erred by allowing such testimony. (People v. Zayas, 1989, p. 574)

Some of these questions might have been resolved had the hypnosis session been videotaped; in 1983, however, at the time of the murders, this was not a common practice. Indeed, when the case came to trial in 1989, the Illinois courts had still not ruled on the admissibility of hypnotically elicited recall. In addition, even if such a videotape had been made, there was simply no way of knowing whether Officer Atkins had come to his near-correct identification as the result of the other factors considered by the court. In the end, there appears to have been no benefit in hypnotizing Officer Atkins. Although his testimony may have influenced the lower court jury in its decision to convict, the problem was that there was no independent corroboration to indicate that his identification in hypnosis was more reliable than his prehypnosis identification immediately after the crime.

In Tardi (1991), the plaintiff was a patient who brought charges of rape and sexual misconduct against a neurosurgeon. The first alleged incident



occurred in 1979. The neurosurgeon's version of the events was that the patient asked him to visit her house to discuss the results of some recent tests she had undergone. By contrast, she maintained that she had not requested this visit and that the neurosurgeon had arrived at her house unannounced. She also stated that she neither told anyone about the alleged rape, nor complained to the police, because the neurosurgeon allegedly threatened dismissal from her job if she did.

In 1980, she commenced treatment with Dr. David Madsen, a psychologist. At intake, he asked her if she had ever been raped; she denied that she had been. In August 1983, she told Dr. Madsen that the neurosurgeon had raped her but insisted that she could not discuss it. When he hypnotized her in September 1983, she provided details of the alleged rape. It is not clear from this account whether her memory of the alleged rape was suppressed, repressed, or whether, believing that she had been raped, she sought hypnosis to confirm her suspicions.

In addition, there were two further alleged incidents with the neurosurgeon when the patient was hospitalized in April 1982 and again in August 1983. At the first of these, she testified that no nursing staff was present, and her roommate spoke no English. At the second, she had two roommates; one was Spanish, and presumably spoke no English, and the other was blind. She did not, subsequent to each alleged incident, tell her family physician about what allegedly transpired. Her first known reporting to another person of the second and third incidents was in a hypnosis session conducted in September 1983.

A fourth alleged incident occurred after her discharge from the hospital following the third one in August 1983. She was examined by the neurosurgeon in his office. She testified that, as with the alleged events of 1979, no other person was present. Then, subsequent to the hypnotherapy sessions, which began in September 1983, she filed charges against the neurosurgeon in January 1984.

In reversing the decision of the lower court, the appellate court stated that there was no reason why the plaintiff could not have changed neurosurgeons any time after the first alleged incident in 1979. The only attempt at independent corroboration of her version of the events was provided by her sister. She testified that immediately after the fourth alleged incident of August 1983, the plaintiff had told her about an incident in which the defendant touched her breasts. The plaintiff's memory was that this touching had occurred in 1982.

In two of the four incidents alleged by the plaintiff, she was alone with the physician; thus it was a classic case of two highly divergent recountings of a set of events. In the other two, the witnesses might have been able to verify the plaintiff's version. At the very least, some attempt should have been made to locate the presumed witnesses through hospital records.



Thus, in the incident of August 1983, there are several potentially verifiable assertions. It was alleged that the physician removed the bedcovers and "began to grope at her vagina," whereupon "she pleaded with defendant to stop" and reported feeling "scattered and falling" (Tardi v. Henry, 1991, p. 4). Again, on the following day, the plaintiff reported that the "defendant became angry; put his hand near her vagina, and said, when he realized that she was wearing panties, 'what is this? You should've been ready for me.' Plaintiff claimed that she then became hysterical, and defendant left her room" (italics added, p. 4). If this is what happened, it is surprising that the roommates did not report it to the nursing and/or medical staff at the time. Each of her two roommates, despite their respective inabilities, would have been capable of verifying (or denying) these memories independently, if they had been asked to do so.

It is difficult to see how hypnosis clarified any of the issues posed by the case of Zayas (1989), which in turn was cited by the Tardi (1991) court. Indeed, the introduction of hypnosis in each of these cases may have muddied waters that were already far from clear. In addition, these two cases do not provide compelling reasons for reconsidering a per se exclusion of hypnotically elicited recall. Nevertheless, courts, not unreasonably, have been troubled by this exclusion and have sought to balance the equation in other ways. One such attempt was by the Pennsylvania State Supreme Court in Smoyer.


Commonwealth v. Smoyer (1984) is typical of cases involving hypnotically elicited recall. Whereas Mack involved memories of events that were clearly high implausible, Smoyer was a case in which there appeared to be a filling in of memory gaps with plausible material. In this case, a man was convicted of aggravated assault, homicide by vehicle, and involuntary manslaughter. The incident occurred as the result of a 1977 high-speed automobile chase of an automobile driven by Mrs. Smoyer by one driven by her husband, which ended tragically. Mrs. Smoyer's vehicle crashed into a telephone pole, killing her. The Smoyer son and a male friend of the family were in her car; they survived. The latter was hypnotized by a police officer 3 months after the incident took place.

Prior to hypnosis, this individual recalled that Smoyer's car had bumped his wife's car twice, prior to the fatal crash. In hypnosis, he recalled that a third bump occurred, just before her car hit the telephone pole. At the original trial, this hypnotically elicited recall was admitted; the appellate court, however, ruled that only his prehypnosis recall testimony was admissible, provided that the prosecution could demonstrate that it was derived from the prehypnosis period, but that his hypnotically "refreshed" recall was not. It should be noted that this



particular ruling was also applied in Zayas. One serious complication that this ruling presents, however, is in the identification of when a specific memory occurred; a person who has been hypnotized is, quite often, unable to correctly identify the source of his or her memory (Whitehouse, Orne, Orne, & Dinges, 1991).


The events of Zayas and Tardi took place at a time when guidelines for the forensic use of hypnosis were only just beginning to be formulated; both the Zayas slayings and the introduction of hypnosis in Tardi took place in 1983. It was not really until 1985 that the Guidelines for the Forensic Use of Hypnosis developed by M. T. Orne in 1979 (copies of an expanded version of them can be found in Laurence & Perry, 1988; Orne et al., 1985) began to be more widely distributed in both court and professional circles. These guidelines insisted on, among other things, videotaping of the entire hypnotic process from the moment that the individual and hypnotist meet initially until the posthypnosis period has terminated. In addition, these guidelines stipulated that prior to hypnosis being attempted, the operator should seek to obtain a complete description of the events in question, using a free-recall technique. This can serve as a permanent record of memory of the crime victim or witness; any alterations of that memory that occur during hypnosis can be duly noted, and disregarded -- unless they are established by independent physical means.

The allure of this approach is that it provides a prehypnosis baseline of memory that has not in any way been altered by the introduction of hypnosis. It should be emphasized, though, that the prehypnosis memory may still include incorrect details. On the other hand, the problem with this approach is that it is possible that even when no new details are elicited in hypnosis, confidence in the memory may be enhanced (see Mickenberg, 1983). A witness who began hypnosis with a highly tentative recall of the events of a crime may become highly confident in his or her recall after hypnosis. Perhaps this problem could be lessened by asking witnesses on videotape, during the prehypnosis baseline period, to indicate their degree of confidence in their memories for each of the elements reported.

The guidelines, which have influenced the thinking of a large number of American courts, are relevant to Boggs's view that the problems associated with hypnosis as a recall method (suggestibility, confabulation, lying, and increased confidence) can be "limited" through the use of guidelines and the adoption of a totality-of-the-circumstances approach. Use of guidelines may permit a person reviewing the videotape of the hypnosis interview to determine whether a novel memory was the product of an inadvertent cue from the hypnotist. They do not, however, prevent the hypnotized crime witness from confabulating; indeed, nothing



can prevent an individual who is fantasy prone from fantasizing, especially in hypnosis. Indeed, if hypnosis elicits novel information, all that one can do in employing the guidelines is to attempt to determine whether it is truth, lies, confabulation, or pseudomemory. Boggs's premise of enhanced credibility of a hypnotic procedure, and of greater reliability through the employment of guidelines, is no more than a chimera.


On the basis of the foregoing considerations, this analysis concludes that Boggs's suggestion to drop the per se exclusion of hypnotically elicited recall as testimony (which exists in 25 out of 30 American state supreme courts that have ruled on the admissibility of hypnotically elicited testimony; State v. McClure, 1993) is likely to lead to even greater legal complications. This is particularly so in terms of tampering with the eyewitness recall, especially by inappropriately increasing confidence in sketchy or inaccurate recollections, thereby making cross-examination more difficult, or in some cases impossible. At the same time, it should be noted that courts that employ a per se exclusion of hypnotically elicited recall recognize exceptions to it (Giannelli, 1995). The most obvious of these is the Smoyer decision, which permits witnesses to testify about their prehypnosis recall (see also State ex rel. Collins v. Superior Court, 1982, which is described in Giannelli, 1995), provided that the prosecution can demonstrate that a memory came from the prehypnosis period.

Then again, the U.S. Supreme Court made another exception in Rock v. Arkansas (1987), when it permitted a defendant who had been hypnotized to testify; this in effect was in direct contradiction of the Arkansas per se exclusion and also the Mack exclusion. The Supreme Court held that such an exclusion was an arbitrary restriction of an individual's right to self-defense. It remains to be seen whether the Mack court's concern with protracted voir dire hearings, with experts on both sides testifying on whether a particular witness should be heard, will become a reality.

There are other exceptions. Scheflin (1994) argues persuasively for the admission of evidence from a previously hypnotized crime victim, for instance, a female patient who alleges sexual relationships initiated by a therapist in the course of a hypnosis therapy session. Here there would appear to be no other course but to permit such a witness to testify; to do otherwise would be a clarion call to individuals wishing to engage in unconsenting sexuality without legal penalty by learning and applying hypnotic induction techniques. In addition, some courts have argued (Giannelli, 1995) that a person who was hypnotized for nonforensic reasons (e.g., a woman treated for weight loss who subsequently recalls that she was abused sexually as a child) should be permitted to testify in court. Such cases tread a very thin line, given the emergence of "recov-



ered memory" therapists who believe that much human distress is the product of repressed, delayed memories of childhood sexual abuse.

In addition, as Giannelli (1995) points out, some courts have argued that a person of low hypnotizability cannot be hypnotized, and hence can testify. This particular decision may turn out to be highly problematic, given that low hypnotizables appear to be affected by a hypnotic context; they may experience little, if any, of the subjective alterations experienced in hypnosis, but they still show an increase in highly confident errors, relative to baseline (Nogrady et al., 1983).

Finally, new challenges to per se exclusions of hypnotically elicited testimony may be looming (Giannelli, 1994, 1995; Scheflin, 1994). In Daubert v. Merrell Dow Pharmaceuticals, Inc. (1993), the U.S. Supreme Court abandoned the approach of Frye v. United States (1923) toward the admissibility of scientifically based testimony. The Daubert ruling is more "liberal" than Frye, because it goes beyond Frye's "general acceptance" criterion and considers such factors as whether the technique has been peer reviewed and published, its error rate (if known), and the existence of standards controlling its operation. It is not clear what will happen to hypnotically elicited testimony under Daubert. One possibility is that it may lead to the gradual erosion of per se exclusions of such testimony; On the other hand, it may mean that hypnosis will continue to be excluded from many courts, not because of "general acceptability" grounds, but on Daubert standards of unreliability (Giannelli, 1995).

An early indication of what may be in store is a recent decision of the state superior court of New Hampshire. The Daubert decision does not require state courts to abandon Frye, and New Hampshire continues to abide by it. Two cases (State v. Hungerford and v. Morahan, 1995) involved the testimony of two women, one charging her father and the other charging a high school teacher of sexual abuse, and both claiming repressed, delayed memories of the abuses. The court ruled that neither could be admitted in court because "the phenomenon of memory repression and the process of therapy used in these cases to recover the memories have not gained general acceptance in the field of psychology, and are not scientifically reliable" (p. 1).

The bottom line, then, is that despite the exceptions noted, a per se exclusion of hypnotically elicited testimony still appears to be the most prudent policy. It is not only a matter of the Mack court's concern with "creating" a witness, nor with the problem of extensive voir dire hearings that would be required to determine whether any particular expert should be permitted to testify. Equally important is the question of the reliability of novel material elicited in hypnosis, which investigators have not been able to substantiate. In short, one might question the benefit of such "evidence" to a legal procedure and wonder whether courts would be more enlightened than police investigators with this additional information that the police were unable to confirm.




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Ein Uberdenken des generellen Ausschlusses von hypnotisch hervorgerufener Erinnerung als rechtsgultiger Zeugenaussage

Campbell Perry, Martin T. Orne, Ray William London, und Emily Carota Orne

Abstrakt: 1993 trat Boggs fur ein Uberdenken des per se Ausschlusses von durch Hypnose hervorgerufener Zeugenaussagen ein. Dieser Artikel analysiert den Fall Minnesota V. Mack (1980), der zur Einfuhrung dieser Regelung fuhrte und die beiden Illinois Falle, die Boggs als Unterstutzung fur ihre Position zitiert. Die wissenschaftlichen Daten uber den Effekt von Hypnose auf das Gedachtnis unterstutzen nicht die Position von Boggs. Statt Grunde fur ein Uberdenken des generellen Ausschlusses zu liefern, legen diese Daten eine Beibehaltung nahe.

Repenser les exclusions per se des rappels hypnotiquement obtenus comme temoignage legal

Campbell Perry, Martin T. Orne, Ray William London, et Emily Carota Orne

Resume: En 1993, Boggs a plaide pour une revision de l'exclusion du temoignage hypnotiquement obtenu. Cet article analyse le cas Minnesota v. Mack (1980) qui a institue cette exclusion et les deux cas de Illinois que Boggs cite pour appuyer sa position. Les donnees scientifiques sur l'effet de l'hypnose sur la memoire ne donnent aucun support a la prise de position de Boggs. Plutot que de donner des motifs pour une revision de cette position per se, ces donnees suggerent que celle-ci devrait continuer.



Repensando exclusiones per se de recuerdos hipnoticamente producidos como testimonio

Campbell Perry, Martin T. Orne, Ray William London, y Emily Carota Orne

Resumen: En 1993, Boggs argumento a favor de repensar la exclusion per se de los testimonios producidos en estado de hipnosis. Este articulo analiza el caso Minnesota v. Mack (1980) que fue el que inicio esta exclusion y los casas de Illinois que Boggs cita para sostener su posicion. Los datos cientificos sobre el efecto de la hipnosis sobre la memoria no aportan sosten a la posicion de Boggs. Por el contrario, en lugar de aportar razones para repensar la exclusion de estos testimonios, estos datos sugieren que debe ser mantenida.

The preceding paper is a reproduction of the following article (Perry, C. W., Orne, M. T., London, R. W., & Orne, E. C. Rethinking per se exclusions of hypnotically elicited recall as legal testimony. International Journal of Clinical and Experimental Hypnosis, 1996, 44, 66-81.). It is reproduced here with the kind permission of the Editor-in-Chief of The International Journal of Clinical and Experimental Hypnosis.