Confidence and Accuracy in Eyewitness Identifications
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The proper APA Style reference for this manuscript is:
BROOKS, S L (2009). Confidence and Accuracy in Eyewitness Identifications. National Undergraduate Research Clearinghouse, 12. Available online at Retrieved April 25, 2017 .

Confidence and Accuracy in Eyewitness Identifications
Department of Psychology University of Central Missouri

Sponsored by: PATRICIA MARSH (


Examines factors and issues that jurors look at when considering eyewitness testimony. Some factors include age of the witness and the confidence of the eyewitness is in their identifications. Examines how police use eyewitness identification to determine suspects through the use of line-ups, show-ups, and photo identification. Also discusses the problems with memory that can occur at the time of the crime, the time elapsed from the crime to the report to the police, and the recall stage when making the identification.

Confidence and Accuracy in Eyewitness Identification

Police and investigative shows are a popular phenomenon and are sweeping the nation. Where many of them have aspects that are false, there are also true aspects to each one. For example, one false “promise” that the viewers receive is the ability to find and extract clear and identifiable fingerprints from rough textures, such as brick. But, where there is fiction, there must be fact. And one of the many factual ideas that are used on popular police and investigative shows are the use of eyewitnesses. The purpose of this study is to examine whether the accuracy of the eyewitness is correlated with their confidence in their identifications.
            Eyewitnesses have been portrayed in, not only, police shows and movies, but also in famous children’s cartoons. If a young child is watching Looney Toons on Saturday morning and Daffy Duck asks Bugs Bunny, “Which way did he go?,” and Bugs answers him, that means Bugs witnessed the person running away and could identify the direction at which he sped off. Therefore, even iconic, yet fictional, cartoon characters can be eyewitnesses.
            In addition to social or cultural norms about eyewitnesses, our basic memory can influence what we report to the police as an eyewitness. The memory process can be divided into three stages. The first is the acquisition stage, followed by the retention phase, and the final stage is the retrieval stage (Merritt, n.d.). The first stage, acquisition, refers “to the individual’s perception of the event, and the entry of the information into the memory system” (Merritt, n.d.). When the witness first sees the crime and inputs the information into their memory, they have entered the acquisition stage. Following the acquisition stage is the retention phase, “during which time elapses before the witness tries to remember the event” (Merritt, n.d.). The time before the witness is questioned by the police or perhaps a jury is the retention phase because time is passing before they have to remember the information. And after the retention phase, the witness has to enter the retrieval stage, in which they try to recall the stored information (Merritt, n.d.). The witness enters the retrieval stage when they are being questioned by the police or are appearing in front of a jury because they are trying to recall the event witnessed.

Human memory may be useful for investigations but it is also flawed.  “Every detail of an experience is not encoded; the human mind can only process a fraction of the rapidly incoming physical stimuli” (Moenssens, Starrs, Henderson, & Inbau, 1995, p. 1171). Because there is so much data coming in, not everything will be remembered accurately. There are other factors that may influence the flow of information to the brain in the acquisition stage. “Event factors include duration of the event, complexity of the event, and the violence of the event witnessed” (Moenssens, et al., 1995 p. 1171).
            In a study (as cited in; Moenssens et al., 1995), the participants viewed violent and nonviolent tapes of an event and the participant group that viewed the violent event had more difficulty remembering and recalling the event than the group that viewed the nonviolent event. The more violent the event, the least likely it is that the witness or victim will remember the event with accuracy. As for the duration of the crime, Professor Burkhout staged an assault during a class of his; the actual length of the assault was 34 seconds, but the 141 witnesses overestimated and the average estimate was almost two and one half to one (2.5:1) (Moenssens et al., 1995). The complexity of the event plays a big part in the encoding and acquisition stage. “Psychological research has shown that complex events are more difficult to recognize and encode into memory than more basic events” (Moenssens et al., 1995). An example, witnesses have an easier time remembering a singular individual at a party as opposed to a group of people at a party. Because of all of the different events that could interfere with the encoding stage, eyewitnesses have questionable reliability.
            The acquisition stage is not the only memory stage that can be affected by outside influences. The retention stage is also affected by issues outside the brain. The retention stage is the information that the brain stores between the time of the crime and the identification procedure. And the retrieval stage is the information retrieved from memory at the time of any of the identification procedure. One issue is that memories fade over time. The longer the time span between the event and the recall, the more inaccurate the memory will be. “The human mind actively fills the gaps created by long term memory loss; this gap filling process introduces inaccuracies into memory for the sake of a ‘complete’ picture” (Moenssens et al., 1995, p. 1172). So, even though an individual may witness an event, the reenactment of said event in their memory could be flawed. Even though a witness believes in their identification, a gap filling process could have taken effect and they could not be remembering as clearly. The human mind is not like a video camera, the images do not stay intact forever.
           The third stage of memory is perhaps the most important when it comes to eyewitnesses and their testimonies. This stage is known as the recall stage. The recall stage is the information retrieved from memory at the time of any of the identification procedure. Several factors influence this stage as well. Eyewitnesses can become victims to social influences. For example, when teachers ask an open ended question to the class, it can be embarrassing to shout out the answer and then have the teacher tell you that you are wrong in front of classmates and friends. “Eyewitnesses, like other people, do not want to appear foolish. By arranging a line-up, police officials suggest to an eyewitness that they have apprehended the culprit” (Moenssens et al., 1995, p. 1173). Because the eyewitness does not want to appear unknowing or inattentive, they may pick an incorrect suspect or individual from the line-up in order to help the police and to get the “bad guy” off of the streets.
            When the police are interviewing a witness, trying to get an identification, the way they are interviewing them can have a significant impact on the witness’s responses. “False identifications result from certain interviewing techniques used by police to retrieve information” (Merritt, n.d.). Because the police are trying to catch a criminal, they are going to do whatever they can to make sure the witness is correct. Therefore, the police do not intentionally interview the witness in a way that could lead to a false identification. The principle that people are influenced by the expectations of other people is referred to as the Experimenter Expectancy Effect (Merritt, n.d.). The Experimenter Expectancy Effect is the “interviewer’s unintentional transmission of information to his subjects, whereby the interviewer can make the subject respond with the desired outcome” (Merritt, n.d.).  The police use identification procedures in order for eyewitnesses to help the police to find a suspect. Two common procedures that are used are the line-up and the photo spread.  The line-up is when witnesses try to pick the suspect out of a group of people. A photo spread is similar to a line-up, but instead of the suspects being shown in person, the witness looks at a series of pictures.

It is important for the police to inform the witness that the suspect may or may not actually be in the line-up or the photo spread. “Failure of the interviewer to advise the witness that the suspect might not be in the line-up or photo spread produces a line-up that is suggestive and unreliable” (Merritt, n.d.). Without this warning, the witnesses naturally assume that the suspect is in the line-up or photo spread and that they have to pick out the right one. Because of this, the line-up can become unreliable. However, the photo spread can also become unreliable due to “photo-biased identification” (Merritt, n.d.). Photo-biased identification can occur when a photo of a suspect is shown to a witness before they make an identification. So, if the police show a photo of the suspect and then show the witness a line-up, the witness may believe that they remember the suspect from the event and not the photo that they saw. Photo spreads are less reliable because typically if a person is shown just one person to choose from, it indicates a higher power of suggestion. If the police are only showing one picture of a man instead of five or six pictures of different men, the eyewitness may decide that because the police think that the man in the photo, or in custody, committed the crime, the witness thinks that they are aiding the police in their investigations. Due to the inherent unreliability of eyewitnesses, the Supreme Court developed a list of factors that have to be considered when determining the reliability of identifications made before the actual trial. “These criteria include: the opportunity of the witness to view the criminal at the time of the crime; the witness’ degree of attention; the accuracy of the witness’ prior description of the criminal; the level of certainty demonstrated by the witness at the confrontation; and the length of time between the crime and the confrontation” (Merritt, n.d.). All of these factors must be considered by the jury when they are listening and reviewing the testimony of any eyewitnesses.
                        Juries are very trusting of the selections made by eyewitnesses. In fact, “studies show that juries tend to over believe eyewitnesses” (Merritt, n.d.). However, in some common law jurisdictions a set of criteria was developed to aid the jury in evaluating the identification of the eyewitness. These rules are used to warn juries that the favorable and believable identification could be a misconception. These rules generally consist of characteristics of the witness to examine if you are a member of a jury. The “set of criteria, subsequently known as the Turnbull Rules…These rules have become widely accepted as the governing test for evaluating identification evidence” (Bromby, MacMillan, & McKellar, 2007, p. 310). These eight factors are the abridged version of the Turnbull Rules:

1) the visibility and lighting conditions at the material time; 2) the distance between the eyewitness and the perpetrator; 3) the duration of observation by the eyewitness; 4) whether the observation of the perpetrator was impeded; 5) whether the perpetrator was known to the eyewitness; 6) the period of time between the observation and the reporting of the incident to the police; 7) the reasons why the eyewitness recalls that the perpetrator was at the scene; 8) the differences between the description of the perpetrator given by the eyewitness and the actual appearance of the suspect (Bromby, et al., 2007, p. ).

            Another factor that could influence the juries is the age of the eyewitness. Because memory is influenced as people age and people associate age with wisdom or experience, jurors may respond differently to eyewitnesses who are younger or older (Brank, 2007; Pozzulo, Lemieux, Wells, & McCuaig, 2006). “On one hand, jurors may believe that children make poor eyewitnesses because they are thought to be highly suggestible and have poor recall abilities. For example, some jurors may deem children to be more honest and naïve than adults, thus providing the most reliable testimony” (Pozzulo et al., 2006, p. 643). Children are only at one end of the eyewitness spectrum, with elderly adults being at the other end of it. Age, and all of the physical and mental disorders that accompany it, can influence the accuracy of the identifications made by elderly eyewitnesses. (Brank, 2007). Because of common stereotypes, elderly people are considered more honest than other age groups. Therefore, the elderly would make better witnesses than other people.
            Juries look at many different factors when considering an eyewitness. But an eyewitness’s confidence in their identification of a suspect is probably the biggest influence on the jury. “Research has shown that as many as 87% of experimental psychologists agree that an eyewitness’ confidence in their identification of an individual is not an indicator of accuracy” (Merritt, n.d.) However, despite this percentage, the majority of juries continue to believe that confidence is an indicator of their accuracy .It is clear that jurors often put a lot of trust and faith in the memories of the eyewitnesses.
            In summary, some of the factors that can influence eyewitness accuracy are age, time, amount and speed of information intake, and juries. The hypothesis to be tested is that the confidence level of the witness (participant) is correlated with the accuracy of their answers and the gender of the witness has some correlation to their accuracy.



The participants in this study included 22 college students (14 males and 8 females) attending the University of Central Missouri. The average age of the participants in this study was 18 years of age. The participants were recruited through the SONA Systems and flyers posted around the campus. The participants were not assigned to any specific conditions and, on their own, chose the day in which they would participate.
            The materials used in this study were a consent form, a short video (21 seconds in length), and a questionnaire about the video. The video can be found at you The video is surveillance camera footage. The video was used to determine which trait was remembered most accurately by the eyewitnesses and how their confidence level related to the accuracy of their answers. The video was chosen due to the fact that there were many conditions to watch and pay attention to. The video was a recording from a security camera in the lobby of a building and recorded were three African American males attempting to break into the building, but the door was locked.
            The questionnaire that was given to the participants had 20 questions regarding gender (i.e., what gender were suspects), race (i.e., what was the race of the suspects), height (i.e., what was the approximate height of the suspects), weight (i.e., what was the approximate weight of the suspects), length (i.e., how long tape/video was), and confidence (i.e., 5-point Likert scale determining the participants confidence in their answers). The true focus of the study will be the Likert scale of confidence and the accuracy of the other questions to determine if there is a correlation between how confident the witness is and how accurate the answers given are.
            When the participants arrive for the session they chose, a consent form was given to them to sign. After the form was signed, a 21-second video clip was shown to them. Everyone was in the same room as the researcher and each participant watched the video at the same time. After the video clip was shown, a questionnaire was given to each of the participants. Once the questionnaire was completed by everyone, the materials were gathered and the participants were debriefed.
            The scores of the surveys were added up based on their accuracy. The questions were scored with one of three grades. A zero was given if the answer was blank, a one was given if some information was given but not enough for identifications, and a two was given if the answer was correct. When conducting the analysis (two way ANOVA) there was no significant main effect of confidence ratings or of gender. There was also no interaction effect between confidence ratings and gender. Main effect for confidence ratings, F(3, 1)= .661, p< .05. Main effect for gender, F(3, 1)= .101, p< .05. Interaction effect for confidence ratings and gender, F(3, 1)= .737, p< .05.

             The hypothesis for this study was that there was a correlation between the confidence of the statements given by the eyewitnesses and the accuracy of the statements. Also, that there was a correlation between confidence and gender. The hypothesis was not supported because none of the findings or effects had any significance. Possible confounds of this study are the small sample size. Because only 22 participants and therefore only 22 surveys, these findings may or may not be easily generalized to the population.


Brank, E. M. (2007). Elder research: Filling an important gap in psychology and law. [Electronic version]. Behavioral Sciences & the Law, 25, 701-716.

Bromby, M., MacMillan, M., & McKellar, P. An examination of criminal jury directions in relation to eyewitness identification in commonwealth jurisdictions [Electronic version] Common Law World Review, 36, 303-336.

Merritt, J. E. (n.d.). Could this happen to your spouse or child? Retrieved April 21, 2009, from

 Moenssens, A. A., Starrs, J. E., Henderson, C. E., & Inbau, F. E. (1995). Scientific evidence in civil and criminal trials. Retrieved from

Pozzulo, J. D., Lemieux, J. M. T., Wells, E., & McCuaig, H. J. (2006). The influence of eyewitness identification decisions and age of witness on jurors' verdicts and perceptions of reliability. [Electronic version]. Psychology, Crime, & Law, 12, 641-652.






Submitted 05/04/2009
Accepted 05/28/2009

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