crime scene tape with blurred forensic law enforcement background in cinematic tone

How forensic psychology finds the truth in unreliable memories

2 May 2022
Providing strategies to support psychological welfare for victims and help prosecute offenders
Associate Professor Helen Paterson's interest in working with witnesses and victims of crime emerged out of being a witness herself while in Sydney on exchange from the University of British Columbia.

If you witness a violent event, your body has a specialised set of responses. The stress hormone, cortisol, floods into blood, readying you for a fight or flight response. As part of what is called the Easterbrook hypothesis, your attention also narrows in on the threat at hand, tunnelling your awareness down to your central vision and losing peripheral details.

Afterwards you may have a pretty good recollection of what happened, though you might lose some specifics over time. You should be able to remember what the perpetrator was wearing and what they said or did. You are unlikely to forget what day it was. These facts are vital for convicting someone in a court of law.

Victims of repeated events ... tend to confuse one incident with another. Then it's Defence 101: if you find any inconsistency in what the witness says, you can completely discredit them.
Associate Professor Helen Paterson, Senior Lecturer in Forensic Psychology

For people experiencing repeated trauma or abuse, such as victims of domestic violence or workplace bullying, all those little details blur together.

They may not be able to remember exactly what the perpetrator said on a particular day or what they were wearing, instead creating a script-like memory of abuse. Tragically, this inability to remember the salient facts can mean the victim is discounted as an unreliable witness, and they struggle to receive justice.

“It is highly concerning to me that the more frequently people are victimised, the less complete their accounts are of each instance,” says Associate Professor Helen Paterson, a Senior Lecturer in Forensic Psychology. 

Lived experience provided academic motivation

Associate Professor Helen Paterson

Associate Professor Helen Paterson, Senior Lecturer in Forensic Psychology. When she moved to Sydney, an arsonist set her her apartment block on fire. This spurred her forensic psychology research into witness memories.

Vancouver-raised Paterson’s interest in working with witnesses and victims of crime emerged out of being a witness herself while in Sydney on exchange from the University of British Columbia in 1998. Fresh off the boat, she was not to know that her “nice cheap place to stay” was certainly cheap, although anything but nice.

“The apartment building had some rather shady people living in it, one of whom was an arsonist,” Paterson says. “He kept setting my apartment building on fire, and the police kept questioning me as a witness. I felt this huge discrepancy between what I was learning in my forensic psychology classes about how witnesses should be interviewed and how the police were doing it.”

The experience motivated her to bridge the gap between the police and the academic field of forensic psychology, to find out what police needed in terms of questioning, and to share with them research about witness memory and the best ways to question witnesses.

Forensic psychology is a massive field. It applies psychological research and theory to the entire criminal and civil justice system. It includes all the people and processes in the legal system, from crime investigation through to trials, post sentencing and rehabilitation of offenders. Researchers might study judges, juries, police officers, witnesses, victims, or criminals.

The Forensic Psychology Lab, headed up by Paterson and Senior Lecturer in Forensic Psychology, Dr Celine van Golde, is where the psychological effects of crime, lie detection, and eyewitness memory are studied by a team of honours students, PhD students and volunteers.

Paterson’s whip-smart team at the Lab are following on from her original research. Their investigations into eyewitness memory are showing just how different memory for one-off events is from memory for repeated or ongoing events.

Part of the problem lies in the way our brains reconstruct memories every time they are recalled. They aren’t placed perfectly in the brain like a filing cabinet. This means there might be slight inconsistencies in how we remember events. A useful analogy may be the difference between cooking from a recipe or from memory. We might add a little more of one spice or another. The basic recipe might be the same, but there are subtle differences in flavour.

One of Paterson’s students, recent Forensic Psychology PhD graduate Sarah Deck, found that people who had experienced repeated events were rated as being less credible than actual liars and those experiencing a single event. The findings are interesting for what they imply: we might assume that people telling the truth will give detailed, specific information about what they experienced, when the opposite is often true.

There is a lot of research looking at repeated assaults on children, but very little on the effect of repeated events on adult memory. I guess there was a belief that adults wouldn’t let themselves be repeatedly victimised, when in fact it is a huge problem.
Associate Professor Helen Paterson, Senior Lecturer in Forensic Psychology

As yet, we don’t have an impartial way of measuring if someone is lying – there’s no Pinocchio’s nose, as they say. We do know, however, that liars tend to create and rehearse a story (or recipe) and stick to it. These rehearsed reports can make them appear confident, highly consistent, and therefore more credible.

The implications for cases of domestic violence or workplace bullying are worrying. In these situations, there is rarely external evidence to verify a person’s claims, so the entire proceedings are reliant on how truthful the victim appears.

Another one of Paterson’s PhD students, Natali Dilevski, has shown that repeated events can affect an adult’s ability to remember specifics of an event. Similar research by others on children’s memories has led to a relaxing of legislation in courts in recent years, so children who have experienced long-term abuse now only need to recount what typically happened in an abusive event. Dilevski’s findings suggest adults who have experienced repeated abuse should be considered under the same legislation.

The assistance of an anonymous donation

Much of the research into domestic violence conducted by Paterson and fellow Senior Lecturer, van Golde, was funded by an anonymous donor who gave $100,000 in 2018. It’s hoped the research program will provide strategies to support ongoing psychological welfare for victims and help them gather the information they need to prosecute offenders. As part of this, Paterson and her team created an app called iWitnessed.

“iWitnessed can help you complete a report straight after the incident, when your memory is optimal,” Paterson says. “Along with your memory account, you can include date stamps, GPS coordinates, and photo attachments. This report can be used to refresh your memory when later questioned. It could also help to consolidate your memory for the crime.”

This is crucial in instances where it might take some time before a victim decides to report the matter to police. The work is ongoing with the app needing constant updating so it stays compatible with new phone updates. And of course, also ongoing, is the need to find truth that ensures justice.

Despite the challenges, Paterson is constantly inspired by what she does and the dedication of those around her: “The lab is just a great environment to work in, with a really talented group of people.”

Written by Cassandra Hill for the Sydney Alumni Magazine. Hero image: istock, all other photography by Louise Cooper. 

More SAM extra