Hypnosis Evidence and False Memories: The case of R. v. Trochym and the Supreme Court of Canada

hypnosis evidence canada supreme Hypnosis Evidence and False Memories TrochymThe Supreme Court of Canada Has made it clear in the case of R. v. Trochym[2007] 1 S.C.R. 239, 2007 SCC 6 that any evidence obtained through hypnosis is entirely inadmissible and banned from admissibility in a criminal trial in Canada. 

In setting aside the conviction and ordering a new trial for second degree murder, the Supreme Court of Canada wrote that post-hypnotic evidence is “presumptively inadmissible for evidentiary purposes” as it does not meet the test for novel scientific evidence that the Court made clear in a decision in R. v. J.-L.J. 2000 SCC 51.

The gatekeeper function of Courts and scrutinization of novel evidence like hypnosis memory:

This type of evidence was the first time the Supreme Court had the opportunity to address its use.  In recognizing the Courts’ gate-keeper function of permitting novel evidence and the use of hypnosis evidence in this case, they wrote, at para 24:

“This case represents the first opportunity this Court has had to consider the admissibility of post-hypnosis evidence. The Court’s framework for assessing novel science ensures that only scientific opinions based on a reliable foundation are put to the trier of fact (J.-L.J., at para. 33), and the same principle applies to scientific techniques. Just as financial results contained in a report must be found to be prepared on the basis of a technique that has a reliable scientific foundation, post-hypnosis memories must be demonstrated to be sufficiently reliable before being put to the trier of fact.  The “gatekeeper function” of the courts referred to in J.-L.J. (at para. 1) is thus as important when facts extracted through the use of a scientific technique are put to the jury as when an opinion is put to the jury through an expert who bases his or her conclusions on a scientific technique. As I will explain, the trial judge’s error was to assume that post-hypnosis evidence is admissible provided that the Clark guidelines are followed.  This is an error, both because the Clark guidelines themselves are insufficient and because post-hypnosis evidence does not meet the requirements of J.-L.J.

The Court continued in far greater detail about this role, and the use of novel evidence. This case serves as an essential tool for lawyers when assessing novel scientific and social science evidence.