During a traditional lineup, eyewitnesses are either shown six photographs of individuals at the same time (simultaneous lineup) or presented one picture at a time (sequential lineup). The paired comparison (PAR) method asks the eyewitness to choose the picture that is more similar to the culprit when shown two photographs at the same time. A technique called signal detection analysis is then used to reveal the structure of the witness’s recognition memory and eliminate unconscious bias.
Credit: Gepshtein et al., Nature Communications
Salk scientists devise a new lineup method to help eyewitnesses more accurately identify suspects
People wrongfully accused of a crime often wait years—if ever—to be exonerated. Many of these wrongfully accused cases stem from unreliable eyewitness testimony. Now, Salk scientists have identified a new way of presenting a lineup to an eyewitness that could improve the likelihood that the correct suspect is identified and reduce the number of innocent people sentenced to jail. Their report is published in Nature Communications on July 14, 2020.
“Misidentification by eyewitnesses is a long-standing problem in our society. Our new lineup method uncovers the structure of eyewitness memory, removes decision bias from the identification process, and quantifies performance of individual witnesses,” says Salk Professor Thomas D. Albright, co-corresponding author of the study. “This study is a great example of using laboratory science to bring about criminal justice reform.”
In the United States, nearly 70 percent of DNA exonerations are due to misidentifications by eyewitnesses, according to the Innocence Project. To overcome this societal problem, research has focused on factors that influence the likelihood that a witness will identify the correct person. One key factor is the way individuals are presented to the eyewitness during the lineup, according to Albright, who co-chaired a National Academy of Sciences committee to examine the validity of eyewitness identification. Albright, an expert in the fields of visual perception and recognition, taps into decades of research suggesting that people commonly misperceive visual events, and memories of those events are continuously augmented and deteriorate over time.
Currently, the two most common (or traditional) methods used by law enforcement are known as simultaneous and sequential lineups. In the simultaneous method the eyewitness views six photographs of individuals at the same time; in the sequential method the eyewitness views six photos, one at a time. The witness then either identifies a suspect or rejects the lineup if no face matches their memory of the crime scene.
The research team sought to create a new lineup method that would help estimate the strengths of memories for each face and eliminate unconscious biases that shape decisions without awareness.
“Traditional lineups just reveal the top choice—the tip of the iceberg. But the cause of the witness’s decision is ambiguous. It may reflect strong memory for the culprit, or it may mean that the witness was not very discerning,” says Albright. “Our new procedure overcomes that ambiguity by revealing the strength of recognition memory for all lineup faces.”
The scientists used a technique, called the method of paired comparisons, which works similar to how an optometrist gives an eye exam: Just like looking through pairs of lenses and stating which lens is clearer, the eyewitness is shown two photographs of individuals at a time and they choose the one that looks more similar to the person they remember from the crime scene. The procedure yields an estimate of the strength of recognition memory for each lineup face. Statistical analysis of these memory strengths then reveals the probability of correctly identifying the culprit.
“Our methods derive from a branch of science called sensory psychophysics,” says Staff Scientist Sergei Gepshtein, first and co-corresponding author of the paper, who founded and directs the Collaboratory for Adaptive Sensory Technologies at Salk. “Psychophysical tools are designed to reveal how properties of the physical world are ordered—or ‘scaled’—in the mind. Our approach allowed us to peek into the ‘black box’ and measure how lineup faces are organized in the witness’s memory in terms of their similarity to the culprit.”
The paired comparison method yields greater information about the identity of the culprit than previous methods. What is more, it offers an unprecedented quantitative index of certainty for individual eyewitnesses, which is what the judge and jury really need to know.
“The conduct of a lineup is just one application of our method,” says Gepshtein. “Another application is selection of lineup ‘fillers,’ which are faces of people known to be innocent. The fillers should not be too similar or too dissimilar to the suspect. Because the new method reveals the perceived similarity of faces, it can be used to optimize the choice of lineup fillers.”
The paired comparison lineup holds much promise as a research tool as well as a practical tool for investigation and prosecution of crimes. The authors hope that the new technique will soon be applied in real police casework, leading to more correct identifications and fewer wrongful convictions.
“Convictions should be based on science, not precedent,” says Albright.
The Latest Updates from Bing News & Google News
Go deeper with Bing News on:
Keeping innocent people out of jail
- Growing Push To Change Bail In NJ; Lawmakers Want Some Kept In Jail
As car theft and shootings spike, Newark Mayor Ras Baraka is leading the push to keep some arrested on gun charges behind bars until trial.
- 2 Arkansas men sentenced to life in prison for killing of informant
Two men convicted in the contract killing of a Malvern woman will spend the rest of their lives in prison for her murder after their sentencing Wednesday in federal court.
- People 'more than their worst mistakes.' Bail has too many languishing in cells |Opinion
These individuals are legally innocent ... by keeping folks employed, we’re preventing crime. In fact, it can actually be more dangerous to hold so many people pre-trial. Extensive research has shown ...
- Horry County bail fund hopes to help the legally innocent buy freedom
The F.R.E.E. Horry County Bail Fund is raising money to bail out people who are legally innocent but remain incarcerated before their trial due to their inability to afford paying ...
- ‘Junk’ Forensic Science Lands Thousands of Innocents in Prison
So- called “expert witnesses,” forensic dentists, ballistics experts, FBI laboratory agents, lie detector examiners, blood stain investigators, are putting innocent people behind bars by ...
Go deeper with Google Headlines on:
Keeping innocent people out of jail
Go deeper with Bing News on:
Science of perception
- Learn to pray and heal at free talk on Christian Science on Saturday, June 4
Learn to pray and heal (A SPIRITUAL ADVENTURE) on Saturday, June 4, 2022 at 11 a.m. Explore pragmatic faith rooted in a spiritual understanding of God and unconditional love on Saturday, June 4, 2022, ...
- University of Rhode names 9 recipients of its 2022 Research and Scholarship Excellence Awards
The University of Rhode Island has named its 2022 Research and Scholarship Excellence Awards recipients. Undergraduate and graduate students, staff and faculty were among the 9 recipients honored ...
- Delaware Museum of Nature and Science opens to the public May 23 after $10.8 renovation
Installation of the new exhibits has been ongoing since the end of 2021. “We’ve completely shed that dusty, old museum perception. The Delaware Museum of Nature and Science is dynamic, engaging, ...
- WIMI Hologram Academy: The Application of Virtual Reality Technology in the Field of Immersive Vision Film and Television
WIMI Hologram Academy, working in partnership with the Holographic Science Innovation Center, has written a new technical article describing their exploration of the application of virtual reality ...
- ‘Skin: Living Armor, Evolving Identity’ exhibition opens at the Science Museum of Virginia
Living Armor, Evolving Identity” exhibit at the Science Museum of Virginia in Richmond offers an immersive experience that showcases how skin shapes ...