top of page
  • Robson Crim

R v Trochym and the Use of Forensic Hypnosis (Part 2/2) - Samantha Harvey

R v Trochym

The case of R v Trochym follows the murder of a young woman in 1992. Police investigators found the body of Donna Hunter, Trochym’s girlfriend, in her apartment and determined the time of death to be in the early morning hours of Wednesday, October 14.[1] The police also noted that it appeared as though the body had been moved eight to twelve hours after the murder to make it look as though the murder had been sexually motivated.[2]

Hunter’s neighbour, Gity Haghnegahdar, told the police that, early in the morning on Wednesday, she heard someone knocking on the door of Hunter’s apartment.[3] Haghnegahdar did not see the person, but heard Hunter open the door. The Crown concluded that, given the time, the person knocking was likely the murderer. Yet, Trochym had told investigators that he left the apartment around 12:30 a.m. He stated he did not return to the apartment unit on Wednesday but did admit to getting his car from the parking garage that day.[4]

Initially, Haghnegahdar testified that she had seen Trochym leaving the apartment on Thursday afternoon. However, after undergoing a voluntary hypnosis session, Haghnegahdar then stated she had seen Trochym leaving the apartment on Wednesday afternoon.[5] The investigators believed that if this were true, Trochym would likely be the killer as Hunter would have been dead by that time.

At trial, the judge admitted the post-hypnosis testimony of Haghnegahdar and allowed the reliability of the evidence to be weighed by the jury. Interestingly, Trochym’s counsel entered into an agreement with the Crown that prohibited the defence from cross-examining Haghnegahdar on her previous inconsistent statements to the police if the Crown refrained from mentioning that Haghnegahdar had undergone hypnosis.[6] The defence believed that the jury might place undue faith in the evidence derived from hypnosis.[7] Thus, not only was the jury unaware that Haghnegahdar originally believed she had seen Trochym leave the apartment on Thursday, but the court did not hear any expert evidence on the reliability of post-hypnosis testimony. Unsurprisingly, Trochym was convicted at trial. On appeal, the Ontario Court of Appeal ruled that the trial judge did not err in admitting the post-hypnosis evidence.

1. The Majority

The majority of the court disagreed with the lower courts. First, the court believed that the Clark guidelines, meant to limit the exertion of influence over a hypnotic session, were insufficient.[8] The Clark guidelines originated from the case R v Clark (1984), 13 CCC (3d) 117, and include eight principles that were intended to improve the reliability of evidence. Some of the principles included that the hypnotist must be independent of the party who requires their service and that the hypnotist should only be given the minimum amount of information necessary to conduct the interview.[9] The court ruled that these guidelines were insufficient as they fail to combat against external sources of influence and the other issues with hypnosis such as confabulation, reduction in a person’s critical faculty and memory hardening.[10] Confabulation is the creation of hallucinated or false memories which may occur as a result of express or implied suggestions.[11] Hypnosis may also reduce a person’s ability to critically examine their memories. Lastly, memory hardening is the process by which a person who has been hypnotized becomes “increasingly, and unduly, confident” in their memories.[12] Often, when witnesses remember a greater number of details, an illusion is created that suggests their memory has actually improved in accuracy.[13] It is important to note that Dr. Elizabeth Loftus, during the Sophonow inquiry, stated that confident witnesses are no more likely than uncertain witnesses to make a correct identification. Loftus explains that this is problematic, as juries tend to believe confident witnesses over uncertain ones.[14]

Nevertheless, the guidelines are all around problematic as they are based on the assumption that hypnosis is a reliable science.[15] The majority used the requirements for testing the soundness of a novel science as outlined in the case of R v J-LJ, 2000 SCC 51. Reliability of a novel science can be evaluated based on: (1) whether the technique can be and has been tested; (2) whether the technique has been subjected to peer review and publication; (3) the known or potential rate of error; and (4) whether the theory or technique used has been generally accepted.

Under the first factor, the court found that hypnosis has undergone numerous studies. However, the studies are inconclusive as the accuracy and the effect of hypnosis are difficult to assess. Experts agree that although subjects may remember a larger number of details under hypnosis, the details remembered include both inaccurate and accurate information.[16] For the second factor, the majority found that the peer review on the area of hypnosis was limited in terms of its use for forensic purposes. Furthermore, experts differed on the extent of the impact of the shortcomings of hypnosis on the witness’s ability to testify. Overall, the weaknesses of hypnosis were well known to the experts and uncontroverted.[17] The third factor, upon analysis, demonstrated that the rate of error is impacted by confabulation, a reduced critical faculty, and memory hardening.[18] Under the last factor, the court concluded that the general tendency of courts is to exert great caution when dealing with post-hypnosis evidence. Thus, the majority determined that the degree of uncertainty that accompanies the use of hypnosis is unacceptable in a court of law.[19] In conclusion, the majority ruled that although hypnosis has been extensively studied and reviewed, the reliability of the science is uncertain and inconsistent.[20]

2. The Dissent

The dissent disagreed and analyzed the hypnosis session to determine whether the post-hypnosis evidence should be admissible. On the day of the hypnosis session, Haghnegahdar was driven to the hypnotist’s office by a detective. The officer testified he was careful not to relay any information concerning the case or make any suggestions during the drive. The officer then gave the hypnotist basic facts of the case and indicated that Haghnegahdar had seen Trochym leave the apartment, but Haghnegahdar was confused on whether it was Wednesday or Thursday. The officer claimed he did not specify which day they would prefer the sighting to have taken place.[21] The officer left, and the session began. The hypnotist asked Haghnegahdar to describe the event of Trochym leaving the apartment. Haghnegahdar recalled more details than before while under hypnosis, such as the fact that Trochym’s clothing looked dark and scary. The hypnotist then asked her to recall what happened next. Haghnegahdar recalled having a snack, taking a nap, and being woken up by her alarm clock. Although Haghnegahdar wanted to go back to sleep, she said that she was worried she would be late to pick her daughter up at 5:00 p.m. from piano class. The hypnotist then asked her to notice what day it was. Haghnegahdar replied that it was Wednesday, because every Wednesday her daughter had piano practice.[22]

The dissent believed that post-hypnosis evidence should not be presumptively inadmissible and the reliability of the evidence should be determined on a case-by-case basis.[23] One doctor stated that the evidence of the subject being able to exercise critical judgment during a hypnosis session indicated that suggestions and confabulation were not occurring, and thus would be evidence that post-hypnotic evidence is reliable.[24] In Trochym, the hypnotist had asked Haghnegahdar several questions throughout the session to which she replied “no” or “I don’t know.” Therefore, the Crown determined that Haghnegahdar was not just guessing and was capable of critically evaluating the new memories.[25] Thus, the dissent disagreed with the majority and believed that the trial judge was correct in concluding that the issue of reliability should go to the weight of the evidence as opposed to its admissibility.

3. Possibilities for The Future

The majority in R v Trochym concluded that the post-hypnosis evidence was incorrectly admitted by the trial judge. As a result, the appeal was allowed, and a new trial was ordered. The majority overturned the decades-long tradition of allowing post-hypnosis evidence to be admitted by ruling that post-hypnosis evidence is presumptively inadmissible for evidentiary purposes. However, although this ruling seems quite straightforward, it does not put a complete end to the use of hypnosis in a judicial setting.

First, although evidence elicited from a witness as a result of hypnosis is presumptively inadmissible, this does not preclude police officers from using hypnosis to gain information that may help them in their investigation. However, the court cautions officers when using hypnosis on witnesses, as the witness may later need to be called to testify and they would not be allowed to testify on questions that were the focus of the hypnosis session. However, a judge may consider admitting evidence that was not the subject of the session.[26] Yet still, the judge has the discretion to exclude the evidence if they find that the detrimental effects of hypnosis outweigh the probative value of the evidence.

While hypnosis is still allowed for investigatory purposes, the science is fraught with complications and is therefore still frowned upon. Furthermore, some allege that too much police reliance on hypnosis would undercut “good police work,” as it was easier to hypnotize people than to dig for the evidence themselves.[27] Yet, there are several cases where investigators used hypnosis to discover monumental leads. For example, in 1976, a bus containing 26 children and a bus driver vanished in Chowchilla, California. The kidnappers had stopped the bus and held the bus driver at gun point. The driver, Frank Edward Ray, and the children were then held captive in a box truck that was buried in a quarry. Fortunately, Ray and the older children on the bus dug their way out of the quarry and ran for help. After this terrifying ordeal, Ray voluntarily underwent hypnosis and was able to remember the license plate of one of the kidnapper’s vans. This information significantly aided in finding and arresting the kidnappers.[28] Thus, fortunately, the Trochym ruling does not completely close off the possibility for officers to employ the use of hypnosis if they imagine hypnosis will be helpful for investigatory purposes as it was in the Chowchilla case. Officers should remain cautious that anything discovered under hypnosis will be inadmissible in a court of law and the elicited information may not contain wholly accurate details.

Second, it is important to note that the majority does not argue that hypnosis will never be admissible in a court of law. The ruling in Trochym was based on their application of the R v J-LJ requirements. Evidently, the information they used to apply these requirements was based on research done prior to 2007. Thus, the door remains open for arguments supported by new research that yields more consistent and positive results regarding the use of forensic hypnosis and its effect on a witness’s ability to testify. However, at this point, there does not appear to be any discernible changes in the field.

VI. Conclusion

After reviewing the origin of hypnosis and exploring forensic hypnosis’ brief role in the court system, the desire to use hypnosis to elicit further details on a case is evident. With the possibility to recover lost details of an incident, hypnosis may be well-equipped to locate and convict criminals. However, the probability of the information gained from hypnosis being inaccurate or influenced by external factors significantly distorts the reliability of the evidence and increases the likelihood of a wrongful conviction. Thus, the importance of the Trochym ruling is clear. Per the majority, the studies on hypnosis have not concretely proved the reliability of the science and the Clark guidelines are insufficient in counteracting the issues inherent with hypnosis. Therefore, until further research can positively show that hypnosis is a reliable science, the use of post-hypnosis evidence is presumptively inadmissible for evidentiary purposes.

[1] R v Trochym, 2007 SCC 6 at para 4 [Trochym]. [2] Ibid at para 6. [3] Ibid at para 5. [4] Ibid at para 8. [5] Ibid at para 7. [6] Ibid at para 21. [7] Ibid at para 23. [8] Ibid at para 27. [9] R v Clark, [1984] 32 Alta LR (2d) 163 at para 23, 55 AR 193. [10] Trochym, supra note 1 at para 55. [11] Ibid at para 42. [12] Ibid at para 44. [13] Ibid at para 43. [14] Sarah Harland-Logan, “Thomas Sophonow”, online: Innocence Canada <> []. [15] Trochym, supra note 1 at para 27. [16] Ibid at para 38. [17] Ibid at para 39. [18] Ibid at para 41. [19] Ibid at para 53. [20] Ibid at para 64. [21] Ibid at para 120. [22] Ibid. [23] Ibid at paras 146, 127. [24] Ibid at para 128. [25] Ibid. [26] Ibid at para 64. [27] Jennifer Vogel & Madeleine Baran, “Does Hypnosis Help Solve Crimes?” (20 September 2016), online: APM reports <> []. [28] Dennis Hevesi, “Ed Ray, Bus Driver During Kidnapping, Dies at 91” (18 May 2012), online: The New York Times <> [].


  • Facebook Basic Black
  • Twitter Basic Black
bottom of page