*Trigger warning is in effect*
Spontaneous false memories are a common occurrence. Well intended, honest people often remember scenes they have not actually experienced, or unwittingly replace a detail of an event by another. In court, this kind of false memories make the pursuit of justice challenging, particularly in sexual assault cases, which often hinge exclusively on witness testimony. Fortunately, psychological research on false memories has advanced greatly in the past decades, and, nowadays, can help jurors and judges decide if a testimony, or a portion of it, is reliable.
Two years ago, on March 24, 2016, Jian Ghomeshi, a radio personality at the time was acquitted of sexual assault charges. In the ruling, the judge called into question the credibility and reliability of two of the three accusers, because, among other reasons, their testimony contained demonstrably false memories. The first accuser testified that Ghomeshi had a yellow Volkswagen Beetle at the time of the alleged assault, when in fact the accused did not own such a car until months later. The second accuser changed the order in which the physical attacks happened (choking first versus slapping first), each time she recounted the incident to the police, the court, and the media. The judge determined that the presence of false memories or inaccurate details regarding the alleged assault cast doubt on the two testimonies. I think this case is worth revisiting, because it is a good example of how psychological research on memory can help in the pursuit of justice.
Psychologists recognize two different kinds of memory1: verbatim and gist. Verbatim memory is literal and superficial; is the kind of memory that stores social security numbers or the lyrics of a song in a language we do not speak. In contrast, gist memory is interpretive and stores meaning; is the kind of memory we use to retain the plot of a movie or the bottom-line message of a news article. Both types of recollections are created, stored, and recalled separately and independent of each other.1 For example, a person can memorize the lyrics of the song Despacito (which is in Spanish), without knowing the meaning of any of the words or what the song is about. Conversely, a witness may not recall the details of a crime accurately (e.g., if she was slapped first or choked first) and still correctly remember the gist of the experience: that she was assaulted by x person.
Independence between verbatim and gist memories mean that false verbatim memories can be created without damaging the true gist memories and vice versa. This is crucial in cases like the Ghomeshi trial, because it implies that the bottom-line meaning of a testimony (“I was physically assaulted by x person”) can still be reliable, even if the details provided by the witness change over time or are proven to be false memories.
In cases where the detail in question does not change the bottom-line meaning of the testimony, a false or unclear recollection of said detail should be insufficient to cast doubt on the entire testimony. For example, if the bottom-line meaning of the testimony is “I was slapped and choked during intimacy without consent,” then it does not matter if the witness has demonstrably unclear recollections as to which happened first. In contrast, if the false or unclear memory is about whether she consented, then the problematic recollection has an impact on the entire testimony.
Another important difference is that gist memories last longer than verbatim ones.1 Thus, a witness should be expected to give a detail-rich and more detail-accurate account of a crime shortly after the incident, but not during a trial, which typically happens months later.
False verbatim memories like the yellow Volkswagen Beetle should also be expected. Psychologists call this type of false recollection misinformation effect. It usually happens when a detail of an autobiographical episode is replaced by other information received after the events. In the Ghomeshi trial, the witness may have falsely remembered that the accused was driving a yellow Volkswagen Beetle at the time of the crime, simply because she saw the picture of the accused next to such a car months later.
Does this mean gist memory is more reliable in court than verbatim memory? No. Gist memories, which rely on interpretation and inference, can also be false. A witness, for example, may falsely remember seeing the accused put a shirt into a washing machine, when, in reality, he or she only saw the accused carrying a shirt into laundry room and then heard a washing machine turn on.1
So, does research on false memories provide a method to tell which parts of a witness testimony are false memories and which are actual experiences? Not yet. However, research findings can help judges and jurors weigh testimonies in ways that are more consistent with the science of memory. Here are some possible guidelines:
- Demonstrably false memories or unclear recollections of details (e.g., colour of a car) should not make courts skeptical of an entire testimony.
- Details in testimonies should be expected to change over time, particularly if the witness was interrogated soon after the alleged crime took place (when verbatim memory is stronger).
- The more time passes after the alleged crime, the less reliable verbatim recollections become.
- Witness testimonies should be expected to contain false memories, either in verbatim, gist, or both forms.
So, what do you think? Do you agree or disagree with any of my suggestions? Feel free to write your thoughts in the comment section.
- Reyna VF, Corbin JC, Weldon RB, Brainerd CJ. How fuzzy-trace theory predicts true and false memories for words, sentences, and narratives. J Appl Res Mem Cogn. 2016;5(1):1-9. doi:10.1016/j.jarmac.2015.12.003.