In contrast, a high-confidence ID is highly accurate , a surprising fact that has only recently come to be appreciated by experimental psychologists. In a recent review of the literature, the authors reported across 15 experiments, suspect identifications made with high confidence were, on average, 97 percent accurate!
Although the high accuracy of an initial ID made with high confidence is important to appreciate, the low accuracy of an ID made with low confidence may be even more important to appreciate. To see why, let us revisit those DNA exoneration cases that so often involve eyewitness misidentification. University of Virginia law professor Brandon Garrett analyzed trial materials for DNA exonerated individuals who had been misidentified with high confidence by one or more eyewitnesses in a court of law.
By itself, that fact only shows that contaminated memory is unreliable just as contaminated DNA evidence is. But in 57 percent of those cases, it was possible to determine what happened on the initial uncontaminated memory test. For every one of those tests, the eyewitnesses were, at best, uncertain. Attributing that error to the unreliability of eyewitness memory is, in our view, pointing the finger of blame in the wrong direction.
Eyewitness memory is reliable when initially tested using proper procedures, but the legal system nonetheless habitually relies on unreliable contaminated eyewitness evidence from later IDs. The sooner police, prosecutors and judges understand that fact, the better off we all will be—including you, if you are ever incorrectly fingered by an eyewitness.
Are you a scientist who specializes in neuroscience, cognitive science, or psychology? And have you read a recent peer-reviewed paper that you would like to write about? Please send suggestions to Mind Matters editor Gareth Cook. Gareth, a Pulitzer prize-winning journalist, is the series editor of Best American Infographics and can be reached at garethideas AT gmail.
Already a subscriber? When they attempt to "fill in the blanks" or offer information they are unsure about, it's usually with good albeit misguided intentions. Eyewitness memories can also be malleable. When a fellow witness shares their memory of an event, others might be inclined to confirm it. They might say they saw something or someone at a crime scene even if they did not.
When a witness is uncertain about what or who they saw, they can be susceptible to suggestions made by other witnesses. Memory decay is also an issue with eyewitness testimony. Research has shown that the stress and trauma of being victimized or witnessing a crime can also influence an individual's ability to accurately recount the details of an event. This is especially true when a weapon was used. In these situations, it's common for witnesses to become focused on the weapon rather than the person wielding it.
The "weapon focus effect" gives victims the ability to accurately describe a gun or knife often in great detail , but leaves them with little to no knowledge of what the perpetrator looked like. Eyewitnesses also have preconceived notions about the type of people who commit certain crimes. Consequently, their bias affects how much information they retain about a suspect.
Eyewitnesses also remembered Black suspects' faces more accurately when they witnessed a crime that is usually associated with other races, such as serial killings. Witnesses also tend to pair the worst crimes with people with darker skin. For less serious crimes, the witnesses were more likely to point to lighter-skinned individuals.
Research has consistently shown that people have difficulty recognizing individuals from other racial or ethnic groups. The "cross-race" effect has major implications for eyewitness testimony and the outcomes of criminal investigations. In the United States, eyewitnesses are presented with a photo lineup and asked if they can identify the perpetrator among the pictures.
Live lineups are also used. In this scenario, the eyewitness is brought in to view the group usually from the other side of a pane of one-way glass , then asked to state whether the perpetrator is present. It's not uncommon for an eyewitness to choose the individual that best matches their memory of the perpetrator. This tendency makes it more likely a witness will identify an innocent suspect who happens to closely resemble the real perpetrator.
One group of students was instructed to choose among the suspects in the lineup. By contrast, the other group received the message that they did not have to make a choice if they didn't think the suspect was in the lineup. The suspect was only included in the lineup half the time.
The researchers found that telling students that they did not have to choose a suspect led to fewer false identifications. The feedback a witness is given also makes a difference. Under the right circumstances, eyewitness testimony can be reliable.
To ensure the information witnesses provide is accurate, the people working on a criminal case must carefully examine how witnesses were questioned, as well as the language that law enforcement used to respond to their answers. Investigators also need to determine whether the individuals providing eyewitness testimony were influenced by other witnesses or the environment around them.
Eyewitness testimony remains a crucial part of the criminal justice system, but it has flaws. The consequences of inaccurate testimony can be serious—particularly if it leads to the conviction of an innocent person. Jurors, judges, police investigators, and legal representatives need to be educated on the factors that affect the reliability of eyewitness accounts and understand the role eyewitness testimony plays in a criminal investigation.
Ever wonder what your personality type means? Sign up to find out more in our Healthy Mind newsletter. Sporer SL. Lessons from the origins of eyewitness testimony research in Europe.
Appl Cognit Psychol. Eyewitness Testimony. Loftus EF. Cambridge, Mass: Harvard University Press; Perceptions and credibility: Understanding the nuances of eyewitness testimony.
Journal of Contemporary Criminal Justice. Innocence Project. Gary Dotson. Updated December Updated January Royal Clark, Jr. Here is the Question Set with key. Some items are filler, some refer to items actually present in the video Present , and some refer to items that were not in the video Absent.
The set of questions without the key that you will give to the students comes after the scoring guide. Students will now answer Yes or No for a list of items. They answer Yes if the item was in the original video and No if it was not. Here is the Key in both list and table format. The student handouts are available here. Here is a table that shows the condition of the various items and details. The question number is in parentheses. Use this table to determine the number correct in each of the four conditions.
Find the average for each condition. In-Class Memory Activity Tell students they will take a memory test. They will listen as you read them a list of 15 words, at a rate of about one word every 5 seconds. They may not write down any of the words as you say them. When you give the signal, the students should write down as many of the words as they can recall in any order. This activity demonstrates several memory concepts.
You want to check to how many students recalled certain words. For these words, have students raise their hands if they recalled them. Asteroid: It was a distinctive word that did not fit in with the meaning of the rest of the words. This demonstrates the von Restorff effect. Needle: You should get a large percentage of the class recalling this word even though it was not on the list. You can show the students the whole list and ask them where they heard it. It also shows the role of schema in guiding recall.
Note: I did not develop this demonstration. A number of variations exist. Roediger, H. Creating false memories: Remembering words not presented in lists. There is a lot of up to date information on eyewitness testimony which I would like to use parts of in an Incident Report Assignment I am doing with several trades students.
Please let me know if I have your permission. Learning about testimonial evidence this way is something I never would have thought of. I have read a lot about Testimonial evidence but this is something that I would want other people to read. APS regularly opens certain online articles for discussion on our website.
Effective February , you must be a logged-in APS member to post comments. By posting a comment, you agree to our Community Guidelines and the display of your profile information, including your name and affiliation. For more information, please see our Community Guidelines. Treating infected people like witnesses to the spread of a virus could improve contact tracing.
Susan MacDonald March 27, Madisen Hurd November 17, Strengthening Contact Tracing Using Witness Interviewing Techniques Treating infected people like witnesses to the spread of a virus could improve contact tracing. We use technologies, such as cookies, to customize content and advertising, to provide social media features and to analyse traffic to the site. We also share information about your use of our site with our analytics partners. Close Privacy Overview This website uses cookies to improve your experience while you navigate through the website.
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If the eyewitness identifies the suspect, then the investigation of that suspect is likely to progress. If a witness identifies a foil or no one, then the police may choose to move their investigation in another direction. This process is modeled in laboratory studies of eyewitness identifications.
In these studies, research subjects witness a mock crime often as a short video and then are asked to make an identification from a photo or a live lineup.
Sometimes the lineups are target present, meaning that the perpetrator from the mock crime is actually in the lineup, and sometimes they are target absent, meaning that the lineup is made up entirely of foils. The subjects, or mock witnesses , are given some instructions and asked to pick the perpetrator out of the lineup. The particular details of the witnessing experience, the instructions, and the lineup members can all influence the extent to which the mock witness is likely to pick the perpetrator out of the lineup, or indeed to make any selection at all.
Mock witnesses and indeed real witnesses can make errors in two different ways. They can fail to pick the perpetrator out of a target present lineup by picking a foil or by neglecting to make a selection , or they can pick a foil in a target absent lineup wherein the only correct choice is to not make a selection.
Some factors have been shown to make eyewitness identification errors particularly likely. It is hard for the legal system to do much about most of these problems. Memory is also susceptible to a wide variety of other biases and errors. People can forget events that happened to them and people they once knew. They can mix up details across time and place. They can even remember whole complex events that never happened at all. Importantly, these errors, once made, can be very hard to unmake.
Some small memory errors are commonplace, and you have no doubt experienced many of them. You set down your keys without paying attention, and then cannot find them later when you go to look for them. Other sorts of memory biases are more complicated and longer lasting. For example, it turns out that our expectations and beliefs about how the world works can have huge influences on our memories.
The result of this lack of attention, however, is that one is likely to remember schema-consistent information such as tables , and to remember them in a rather generic way, whether or not they were actually present.
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