To what extent do you agree?
By: Anita Patel, April 1999
When hypnosis was first introduced into the criminal justice system it was considered a method to aid in witness recall and it was claimed to be a brilliant advance in police investigations. The pledge of hypnosis as a memory aid in a forensic context was advertised by its use in high profile cases such as the Boston strangler case where the techniques provided information that led to conclusive physical evidence and made the offenders of crimes fearful of prosecution.
This use of hypnosis has led to increasing physical evidence in the criminal justice system. However problems arise when courtroom testimony was based solely on recall following hypnosis. Lacking physical proof to corroborate fully the fragmented, uncertain memories of victims, witnesses or defendants; law enforcement agencies have tended to use hypnosis to aid memory for testimony, to the events in question. In the absence of corroborating evidence this use of hypnosis, looks at the debate on whether the technique produces bona fide remembering of forgotten events or whether it changes memories and thus evidence so that cross examination would be less effective of finding the real truth.
These issues have been the subject of legal concern within the criminal justice system and expert testimony based on forensic, clinical and scientific evidence that has been important in this controversy.
The following items should be considered to evaluate the usefulness of hypnosis in a forensic setting:-
1) The reliability of information obtained through hypnosis
2)Whether hypnosis increases the likelihood of pseudomemories
3)Whether hypnosis makes the individual’s recollections more susceptible to alternations due to subtle cues or expectations.
4)Who should carry out the hypnotic procedures
5)Whether hypnosis alters the certitude of what can be remembered independent of the accuracy of memories.
6)Whether there are procedures that might increase the probative value of ‘hypnotically refreshed’ recall relative to the risk of distorting memories.
7)Whether one technique for recall in hypnosis is more or less effective than another in either enhancing or distorting recollections.
8)Whether a jury is likely to be unduly affected by knowing that testimony based upon ‘hypnotically refreshed’ recall.
Orne et al cited in Wells and Loftus (1984).
It is generally assumed that hypnosis can be described as a change in an individual’s ‘state of consciousness’. It shares some of the similarities associated with sleep except for that the altered state shows a high level of arousal, unlike sleeping individuals , who are less responsive to most stimuli in their environment.
One of the most fundamental issues underlying the controversy surrounding hypnotically induced recall in the criminal justice system is the extent to which hypnosis can serve to improve memory over and above that possible from attempting to remember without the aid of hypnosis. This is termed Hypnotic Hyperamnesia. Studies into this area have shown that if the material to be remembered is not particularly meaningful, hypnosis does not aid recall beyond normal non hypnotic recall levels. However if the to be remembered material is contextually meaningful, hypnosis appears to provide a way of obtaining increased recall performance (for some of the individuals with some of the situations).
Following a traumatic episode, Orne believes that hypnotism may lend itself to the appearance of new lines of investigation. It must be born in mind however that it is possible for witnesses to lie under hypnosis. Therefore the common view that hypnosis provides wholly correct information is in essence incorrect. As well as outright lies, a person while under hypnosis may create memories for a period of time that they cannot fully remember. One possible explanation for this may be due to the communication between the hypnotist and the subject.
It should be recognised that a hypnotised person is more relaxed, more compliant and more suggestible than when not hypnotised. The consequences of this include:-
1)The individual may suspend their normal critical judgement and say things of which they are unsure.
2)The individual may comply with the requests from the hypnotist for more information, even if no actual information is available in their actual memory.
3)The individual may respond to suggestions made by the hypnotist and incorporate such information into what the person believes to be their original memory.
Ainsworth (1998, p116).
Given that hypnosis has its advantages its implementation is potentially hazardous when employed on eyewitnesses. Orne says that pre-hypnotic beliefs are important. If an individual believes that their memory should get better under hypnosis then they will show this behaviour when they are hypnotised. The information acquired through this could be valuable if the details are accurate and could be used by the police in their investigation. It could however produce confabulated information as the individual believes that their memory will improve and will do so whatever, this may produce an memory which is not an actual true memory.
The leading of the hypnotist will further cause problems as it may make the individual provide information which the hypnotist wants rather than the true information. This has been proven by Orne (1981) when even the slightest communication from the hypnotist influenced the subject. What’s more, neither subject nor hypnotist are aware of this happening. To a certain degree bias may be excluded from practice but that is it’s limit. It is impossible to eliminate leading questions/bias in actual practice.
Who should carry out the hypnotic interviews? There has been many discussions over this question but it is believed by the researchers that appropriately trained psychologists/psychiatrists or others in the mental health field should be the only individual’s employed to carry out such sessions. This is important as the individuals hypnotised may remember or believe to remember very distressing events which may trigger other mental health disorders. Obviously a Police Officer is not knowledgeable about such symptoms or signs and cannot propose treatment as a mental health professional can.
However Reisser believes that police officers are capable of conducting hypnotic interviews effectively, after suitable training (Reisser, 1989) and disregards Orne’s apprehension as he argues that credence should be put with the officers to administer the interviews correctly (cited in Ainsworth, p177).
Any professional who conducts hypnotic interviews might mistakenly cue or lead a witness whilst in a session.. With police officers it could be that any believes that they may have on the inquiry could be transferred on to the hypnotised witness and become ingrained on to their memory of the event. If the witness is later asked for testimony in court, the witness will find it difficult to divide the initial memory from the resultant statements made. This problem is one of the main concerns in the use of forensic hypnosis. Loftus et al has shown repeatedly that original memories can be altered by subsequent misleading information. (Loftus from Ainsworth p120).
Most of the subjects in the Loftus experiments were carried out on ‘normal’ individuals in a normal’ world state of consciousness thus, if it is easy to alter their memories, then the problem is exacerbated if the person has been hypnotised. (Ready, 1986 cited from Ainsworth p120).
As suggested before witnesses under hypnosis are more relaxed, more compliant and more suggestible. These factors make it likely that a witnesses memory will be altered by the hypnotic interview itself. If witnesses feel more relaxed then they will suspend their critical judgement or lower their decision threshold. If this is the case then when in a ‘normal’ state witnesses may only provide information of which they are hundred per cent certain of. If pushed by a interviewing officer they will not volunteer the information. But whilst under hypnosis their more relaxed state could mean that they are more likely to volunteer information about which they are unsure of. In their relaxed state the subject may have an immediate desire to please the hypnotist over the possible long-term consequences for an innocent defendant. (Ainsworth, p120-121).
Even information that the individual -whilst not in hypnosis remembers in hypnosis has been found to be included into the initial memory. This is not real accurate information and so it cannot be claimed to be a true development of their memory.
There are many hypnotic techniques that can be used in an session. The hypnotist may use a technique such as asking the individual to imagine that they are watching a video recording of the event/incident that occurred. This particular hypnotic technique has frequently been used in forensic settings (Reiser, 1976 cited in Wells and Loftus). The witness may be instructed to stop the video tape at appropriate points and to examine the scene in more detail. The strategy maybe useful but leads the witness to believe that the memory works like a video recorder and such an analogy is not satisfactory. It presents an implicit suggestion that the details of the event are in the persons memory and an explicit suggestion that the recollections that are obtained in hypnosis will be vivid and factually accurate (Orne cited in Wells and Loftus).
It has been found that witnesses who have been hypnotised often claim after that their new recollections took place earlier rather than followed the hypnotic session. This looks at the issue of hypnotically refreshed recall as used for testimony in a court of law.
It has been argued that hypnotically refreshing a witnesses memory is not reliable so the testimony based on it not reliable, thus not usable as evidence. The other argument is that hypnosis is one of the several procedures to refresh recall and should be permitted under the rules of evidence and left to the ‘trier of fact’ to decide the credibility and reliability of evidence brought about.
A legal review written by Diamond (1980) (Cited in Wells and Loftus) concludes that the danger of misconduct with the pre-trial use of hypnosis is very important and that no witness should ever be allowed to testify in a case where it has been used to ‘refresh’ recall previously.
The degree to which a witness or victim feels confident about remembered details of an event is central to testimony in court but less important for investigative purposes, especially when corroborating evidence can be found. In court the confidence of an accuser or witness places in his/her memories has an effect on the extent to which the individual can withstand cross-examination and upon their perceived credibility.
Sheeham and Tilden (1983) and Dywan (1983) (cited in Wells and Loftus) found that the confidence that subjects placed in their memories, as well as the degree to which they were certain that their answers were correct, was significantly increased for all subjects by hypnotic procedure. The effect was stronger among the more highly hypnotisable individuals. This was not braced with an increase in accuracy beyond that found for non hypnotic remembering.
Putham (1979)(cited in Wells and Loftus) found that subjects who underwent hypnosis believed that they were more accurate than they would have been without hypnosis. It has been found through studies that hypnosis cuts off accuracy of memory from the confidence that a person places in their memory reports. With non-hypnotic memory, confidence and accuracy are generally correlated.
In summary, the data suggests that hypnosis creates changes in memory and the confidence placed in it, relative to non-hypnotic recollections. These changes are desirable, because hypnosis frequently increases inaccurate as well as accurate memories and the changes are not easily undone once the technique has been used.
These changes are likely to be enhanced in the applied forensic settings, where the witness to be hypnotised is intensively motivated to help the authorities, where the belief is held that hypnosis will extract accurate recall or recognition and where the hypnotist reinforces the subject for material of interest that is brought forward in hypnosis. Furthermore, after hypnosis has been used to refresh the recollections of a witness or victim, there is no way of determining whether the new memories or the increased confidence in them shown by the witness are due to accurate reports of previously unremembered events. The new memories could easily be pseudomemories and , the so called new confidence is wrongly used.
Although hypnosis holds some possibility for increasing accurate recall in some situations, these other changes, as well as the potential for increasing biasing resulting from undue suggestiveness, makes it not appropriate to recommend the use of hypnosis before to testimony in court. Testimony based on ‘hypnotically refreshed’ recall may seriously endanger the procedures within the criminal justice system that are designed bring about a fair assessment of the evidence.
The current use of scientific knowledge is in accordance with the rulings of a number of courts, that memories recovered through hypnosis are sufficiently unreliable so that their use is excluded as eyewitness testimony in criminal courts. It is appropriate at the current time to restrict the forensic use of hypnosis to investigate situations where the potential gains are likely to be greater than the risks providing that suitable guidelines are followed.
Guidelines include the hypnotist being a suitably qualified:-psychologist, psychiatrist or other mental health professional who has had training in both the clinical use of hypnosis as well as in its forensic applications.
The hypnotist should not cue or reinforce the witness. For this reason it has been argued that a complete video recording of the session should take place including the prehypnotic interview as well as the actual hypnotic session. The video should view both the hypnotist and the witness, so that it can be seen if any cueing verbally or non-verbally took place.
It is also recommended that only the witness and the hypnotist should be in the room whilst the hypnotic session is taking place so that no other cueing from anyone else is picked up by the witness. If the hypnotist needs to communicate with others investigating the case then a break should be incorporated for discussion.
A post hypnotic discussion should take place between the hypnotist and the witness to discuss the session and address any fears or concerns the witness may show, this should also be video recorded.
Appropriate hypnotic techniques should be employed with appropriate memory retrieval techniques (use of free narrative flow where possible), as well as incorporating a test of suggestibility to allow for assessment of the subjects hypnotic responsively.
Additionally, it should be suggested to the witness that it would be beneficial if they attended a clinical follow up in the future. The reason being that they may become distressed by the experience of the hypnotic session.
Bibliography
1)Ainsworth. P. (1998) Psychology, Law and Eyewitness Testimony
John Wiley
Refences cited:- Reisser, 1989
2)Berry.M. J, Robinson.C, Bailey.J. (1999) The Use of Hypnosis to Recover Evidence:Issues and Implications
Currently in press
References cited:- Virgo, 1991,1995, Gibson, 1977, 1995
3)Frankland. A , Cohen. L. (1999) Working with Recovered Memories. The Psychologist, v 12, no 2,82-83
4)Mc Conkey. K. M , Sheeham. P W. (1995) Hypnosis, Memory and Behaviour in Criminal Investigation
Guilford Press
5)Wells. G , Loftus. E, (1984) Eyewitness Testimony-Psychological Perspectives
Cambridge University Press. Chapter 9 Hypnotically induced Testimony- Orne, Soskins, Dinges and Orne
References cited:- Orne, 1981a, Reisser, 1976, Putham, 1970, 1980, Sheeham and Tilden, 1983, Dywan, 1983, Diamond, 1980