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Memory, recovered memory and false memory in sexual assault and homicide investigations: Part 1

February 16, 2023  By Peter Collins

At least three or four times a year I am consulted by investigators who encounter an allegation of sexual assault(s) and/or murder(s), and the victim or witness only recently started to recall the events that led to their disclosure.

There has been a great deal written over the past couple of decades about the phenomenon of the recovered memories of childhood sexual abuse. When recovered memories are shown to be false, they are regarded as a false memory. Many of these memories are iatrogenic in nature – they are suggested, supported, validated, encouraged and “recovered” through unproven and pseudo-scientific practices and methods of therapists, who are often well-meaning. There are some individuals who can also develop a belief and a memory regarding a trauma, that is internally motivated and generated, rather than being the result of a suggestion during counselling or therapy. In order discuss recovered memory, one must examine what memory is and how it works. This is a daunting task because memory is complex and is not a single process.

A simple model is to regard memory as involving a series of systems, with each system operating on its own set of principles. Generally, there is sensory memory, short-term memory and long-term memory.

Sensory memory

Sensory memory (also known as sensory registers) is a collection of memory stores that correspond with each sensory modality – vision (iconic memory), hearing (echoic memory), touch (haptic memory), as well as taste and smell. It is the storage of information that we receive from our senses.


Sensory memory may be accurate, but it exists very, very briefly. Before memories go into short term memory storage, they sit in sensory memory. While some types of sensory memory are in our minds for up to four seconds, other disappear within milliseconds. During the brief time that this information remains, the brain only pays attention to the most salient aspects. The sensory registers allow us to only hold this information for these brief periods to determine if it is worthy of further attention. That information is matched to recognizable patterns and assigned meaning. Only the most significant features are transferred to the next stage, short-term memory, for further processing.

Short-term memory

Short-term memory is where conscious thought occurs. When a person recalls an event, performs addition mentally or reads a string of words, the information to execute these functions is held temporarily in short-term memory. Information in short-term memory remains longer than that held in the sensory registers, but much of the data is forgotten in less than a minute unless some further processing occurs. Another characteristic of short-term memory is its capacity – the amount of memory that can be held in an active state. Research has shown that it is somewhere around seven items or less.

These false memories can have devastating consequences as they can lead to false accusations and wrongful convictions.

To prevent short-term memory loss, one must repeat the information to keep it active and prevent it from being displaced by new material. However, before the brain can retain material, it must transfer it to long-term memory. Like the transfer of sensory memory to short-term memory, information that relates easily to existing memories has a better chance of being retained compared to new data.

Long-term memory

Long-term memory is the storage of information for an extended period. Unlike the limited capacity of short-term memory, the amount of information stored in long-term memory is theorized to be unlimited. Typically, when people talk about memory, they are referring to the material held in long-term storage.

Confused? Well, there is more to consider.

Procedural memory represents knowing how to perform certain activities, such as driving a car, using a computer, throwing a baseball or shooting a puck. This is the memory of skills. This knowledge is unconscious and procedural.

Declarative memory refers to facts and knowledge we remember—the capital of Nova Scotia, the location where a birthday was celebrated, or, perhaps, what a robbery suspect was wearing—that are consciously recalled. Sometimes the significance of an event helps encode the memory. Significance is truly important. For example, most individuals can remember their first kiss. How many individuals remember their 14th kiss?

Recovered memories and false memories

As noted above, when recovered memories are shown to be false, they are linked to what is called “false memory syndrome”. False memories are memories of details or events that were not experienced. These pseudo-memories usually arise in the context of therapy and are often quite vivid and emotionally charged. The person truly believes their memory of the events are accurate, even in the face of proof otherwise. These false memories can have devastating consequences as they can lead to false accusations and wrongful convictions.

The concept of false memories was due to two intertwined developments that unfolded in the 1980s and 1990s that are now referred to as the “memory wars”. There was heated debate on the existence of unconscious repressed memory. One theory was that because of the overwhelming nature of traumatic experiences, memories of these experiences were unconsciously blocked and not accessible. Naïve and misinformed counsellors believed that the key to uncover these unconscious repressed memories was through therapy.

Also contributing to the memory wars were high-profile cases involving abuse in daycare facilities. An infamous U.S. case was the McMartin preschool case which took place in Los Angeles in 1983. In this case, hundreds of children reported to have been sexually abused by seven teachers. There were videotaped interviews with the pre-school children that were conducted by a social service agency. The interviews showed extreme forms of suggestive pressure toward the children, such as asking them about details that were never mentioned during any prior statements provided by the children. The charges were eventually dropped because jurors concluded that the leading interviews contaminated children’s testimonies.

Occasionally, false memories involve other outrageous allegations, including satanic ritual abuse. A notorious Canadian case occurred in Saskatchewan in 1992. A woman in the community of Martensville alleged that a woman who ran a local daycare centre had sexually abused her child. After the police began to investigate, allegations began to snowball and ultimately over a dozen persons, including five police officers from three different services, faced over 100 charges connected with running a Satanic cult called The Brotherhood of the Ram, which allegedly practiced ritualized sexual abuse of numerous children at a satanic church.

The son of the day care owner was tried and found guilty of sexual assault, but not on the scale that had been alleged. An RCMP task force subsequently took over the investigation, concluding that the original inquiry was motivated by “emotional hysteria”. Also, of note, was that the interviews of the children involved questions that were leading in nature, and the children were praised for giving incriminating answers.

Looking ahead

In the March/April column, I will explore more of why false memory occurs, how to recognize it and provide case examples.


  1. Loftus, E. & Davis, D. (2006). Recovered memories. Annual Review of Clinical Psychology, 2, 469–498.
  2. Otgaar, H. et al (2022) A court ruled case on therapy-induced false memories. American Journal of Forensic Sciences. DOI: 10.1111/1556-4029.15073
  3. Otgaar, H. et al (2019). The Return of the Repressed: the persistent and problematic claims of long-forgotten trauma. Perspectives on Psychological Science 14(6) 1072–1095.
  4. Radvansky, G. (2021). Human Memory – 4th edition. New York: Routledge.

Peter Collins is the operational forensic psychiatrist with the Ontario Provincial Police’s Criminal Behaviour Analysis Section. He is also a member of the crisis/hostage negotiation team of the Toronto Police Service Emergency Task Force. Dr. Collins’ opinions are his own. Contact him at

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