Luus, C. A. E., & Wells, G. L. (1994). The malleability of eyewitness confidence: Co-witness and perseverance effects. Journal of Applied Psychology, 79, 714-723.
Luus and Wells (1994) provide an excellent study regarding the extent to which confidence of eyewitnesses can change and vary based on information they receive from various sources, especially regarding information about others decision making processes for lineups. Their study incorporates a very social psychological design with a traditional eyewitness identification approach in which participants are shown a crime video, asked to identify the person they saw commit the crime from a lineup, and then indicate how confident they are in their decision. The twist with this study is they then told participants, assigned to various conditions, information about other people's decisions on the lineup (i.e., same, different, etc.). Thus, participants receiving information indicating that another person picked the same face out of a lineup that they did, exhibited an increase in confidence. Those hearing from the confederates of the experiment regarding people who disagreed with their decision or rejected the lineup, indicated much lower confidence statements relative to other conditions of the experiment in which agreement occurred.
In their next experiment, the researchers showed the videotaped lineup administrations complete with the decision, confidence, and induction of false information recorded from Experiment 1, to a new sample of participants to rate how accurate they perceived the participants in the various conditions in Experiment 1 to be regarding the decision made. They found that when viewing a recording of the inflated confidence conditions, participants predicted higher accuracy to result based on their confidence statements, compared to recordings of the confidence deflated conditions.
This study provides a nice review of the malleability of confidence judgments and also tells a cautionary tale of how law enforcement officials and others who may influence eyewitness confidence with information or positive feedback regarding decisions made, should consider the potential harmful impact of the information they provide to witnesses.
--By DJP
Many conclusions were drawn from this paper, although I am still trying to figure out how. The studies were not thoroughly explained, so I still do not understand completely what went on. It was found that those participants who were led to believe that other eyewitnesses chose the same perpetrator, gave more detail in description, and were more confident in their identification than those participants who were led to believe another witness disagreed with their identification. This is easy to understand, as there are many studies in which touch on the same ideas of malleability from one participant to the other. But, I am still a little shaky on all the details leading up to this conclusion. The introduction and discussions were written well, but it seems that the methods and results sections were hard to follow. This may be due to the complexity of one participant here, one there, some alleged participants, ect. But it also may be due to my lack of knowledge in the area.
In conclusion, malleability in a participant's confidence is a true problem among eyewitnesses and other studies alike. So, disclosing information such as what a previous eyewitness concluded to another eyewitness should never be allowed. This is almost like disclosing information about the alleged perpetrator involving their previous record, ect. There needs to be a policy to control this idea in our system.
For the seconds of Dwight’s articles, I chose to read The Malleability of Eyewitness Confidence: Co-Witness and Perseverance Effects. It followed what I thought appeared to be a very well planned study, through the setup of the fake experiment, to the organization of the thievery and the ensuing phone calls, and the amounts of data from the nine different options for one variable. I believe the nine options allowed for more accurate and certain conclusions than running multiple separate studies. Surprising to me, however, was that even with all of the steps the administrators of the experiment took to help guarantee incorrect identifications in the lineup, three percent of the subjects still opted for the “not present” selection (which was correct), when it wasn’t even presented to them. To be completely honest (though it would probably change as a result of my experiences in this seminar), I probably would have selected one of the members of the lineup if they even looked remotely similar, although it’s difficult to know for sure when not being put in the position. The experiment is based on the idea that a witness’s confidence in their identification can be molded after hearing the results of a co-witness’s lineup, even though nothing changed in their individual identification. I thought the experimenters’ identification and addressing of possible flaws, as well as the reasoning skills displayed in the discussion of their analyses and explanations of different outcomes were very thorough. It seemed like they understood their experiment inside and out (something that should be expected), and really put a lot of thought into the “Why?”, instead of just presenting their results, and that impressed me. It was also interesting to me that, according to the data, “early information (immediately after the identification decision) is likely to have much greater impact than later information”. While, at first, it seems odd that even with the same end result of knowledge of the co-witness’s identification, that if the administrator initially makes a “mistake” in their leaking of the information, that that affects the witness’s confidence more than the truth, if its exposed later.
The author’s identification of the witness’s reaction to a co-witness’s implausible selection, and resulting perseverance of high confidence in their decision is a pretty telling piece of information. As stated in the article, they “interpret this finding to mean that these confidence shifts are not due to simple, mindless conformity but rather are the product of a deeper analysis of the meaning of the co-witness’s behavior.” This, again, appears to be a significant observation to me, as it does seem to indicate that this phenomenon isn’t solely just the witness doubting themselves regardless, but actually applying reasoning to the situation, along the lines of “I didn’t get a clear shot of the suspect, but I know I remember [x, y, & z],” and if the co-witness’s identification is of a different suspect, but matches the x, y, & z that the witness recalls, that they trust that the co-witness got a better look at the suspect, whether or not they did in reality.
One small problem I had while reading this study was that they didn’t mention anything about controlling the participants’ possible discussion of the crime and the description before they were presented with the lineups, which I believe may influence the results. While I don’t think that subjects would have said anything along the lines of “Did you just see that brown eyed girl with the short blonde hair and the big nose just steal that piece of equipment?”, the setup of the experience still leaves that possibility open, and if the suspects discuss the event before being subjected to the lineup, there is a chance that results could be somewhat skewed. A problem I had identified in the second experiment, but was later addressed, was whether or not those watching the video of the witnesses were exposed to the information about the decision of the co-witness. This is another example, in my eyes, of how well run and thorough the implementers of this study were.
SB
Many people believe that a confident witness is an accurate one; this is an easy point of view to understand since it is normally easy to place a greater amount of trust in someone when they give a confident statement vs. one with little confidence. The strength of believing an eyewitness (who is identifying a culprit from the lineup) is expressed though the eyewitness’s confidence. The way the witness makes their statement, their body language, expression, all of this plays into confidence. According to a previous meta-analysis, the relationship between accuracy and confidence is weak, only accounting for approximately 6% of variance in the actual accuracy of eyewitness identification.
This article talked about co-witness information, this being an eyewitness passing information of the event onto another eyewitness who also saw the event. I learned that this passed on information can either be directly passed on or passed on by a 3rd party such as by a police officer. I believe that officers should be educated in knowing that they should not explain information to one witness that another witness has said.
It was pointed out that much research on eyewitness confidence has previously been toward linking accuracy with confidence, whereas this article described that “confidence main-effect problem” is possibly of more importance. The “confidence main-effect problem” was said to be the thought that traumatic events can cause a shift in the eyewitness‘s confidence without having a clear affect on confidence. It was also pointed out that in some cases; witnesses who are clearly inaccurate show forth much confidence, thus, pointing back to the thought that this relationship between accuracy and confidence is actually rather weak. This article was good for me to read because I was under the impression that this relationship had a stronger correlation. Experiment 1 showed that eyewitness confidence malleability goes both ways, it is bidirectional. Some witnesses’ ideas may be strengthen by co-witness information whereas others may disagree with it. Overall I learned that eyewitness confidence is definitely easily influenced and this should be taken into account when dealing with witnesses.
SD
This post is a little late, but I am at the American Psychology Law Conference right now and internet is a little difficult to get. Anyway, the other confidence/accuracy articles are interesting. It is amazing to think that other witnesses can influence a witness’s confidence so much. I thought the research design was well controlled and isolated a variety of factors. I also thought it would be nice to write down some of the research that is being presented at this conference in this post to share with the class.
A lot of the research here has been focused on wrongful convictions, which is a subject we have talked about a lot recently. One of the other interesting talks here focused on consequences of wrongful convictions. An interesting finding from this talk was that participants did not seem to want to believe that a defendant who had falsely confessed was innocent. This was an interesting finding because it showed the power of false confessions and the effects that they have on jurors. Another interesting talk concerned police and their knowledge base. A somewhat troubling finding by one of the talks was that 80% of law enforcement officials are not familiar with the Guide that we have discussed extensively in class. I found this number to be very difficult to fathom. It seems like eyewitness identification researchers are making a great deal of progress, but to see a number like this is very troubling. Another talk I attended dealt with the CSI effect and juror perceptions. The CSI effect did not affect participants’ guilt ratings in a mock trial, but it did affect their beliefs in some of the evidence presented in the case. Some interesting research lies ahead for this particular phenomenon. Also, there has been a lot of research presented dealing with lineup administration and lineup construction. Much of the research being presented here has a great deal of bearing on our seminar, and I would be happy to talk with anyone about research that I saw here.
HC
The study done by Luus and Wells on the malleability of eyewitness confidence looks at how eyewitnesses are easily influenced and whether confidence levels have anything to do with accuracy (1994). Past studies have indicated that if the confidence level of eyewitnesses is high, people see their testimony as more accurate. I can see how this would happen, especially if I did not know about the weaknesses of the brain and memory. As a person of the jury, I am sure confidence levels of eyewitnesses play would play a large role in whether or not they believe them.
In reality, the empirical relationship between eyewitness confidence and accuracy is not very good (Bothwell, Deffenbacher, and Bringham, 1987). When an eyewitness picks the culprit form a lineup, they express their confidence by making statements like, “it might be him” or “I am positive it is that one.” Social factors can influence the confidence of eyewitnesses, distorting their actually memory. The brain is malleable in many different ways, so I see no reason why eyewitness confidence would differ.
The current study looked at how co-witness information influenced the witnesses’ memory. The study distorted witnesses’ memory after they made their decision and ensure that false identification rates were near 100%. They took many steps to ensure that this would happen by giving a brief and poor look at the culprit and not having people in the lineup look similar. I am not positive why they did this, but I think it had something to do with not looking at accuracy rates. Upon further reading, I found that having all the eyewitnesses be incorrect, it made it easier to deflate their confidence than to inflate it. The confidence of eyewitnesses is bidirectional, but the experimenters expressed that there are limits to it. They were unable to reverse confidence inflation. Eyewitness confidence is greatly affected by co-witnesses decisions.
When a co-witness picks the same person and it is expressed the witness, confidence goes up and they feel better about their answer. This works the opposite way as well, bringing to light the idea that confidence malleability is bidirectional. I can see how this would happen especially if you knew the other witness. If you both saw the event from the same area and at the same time, you would think that you both have the same information in you head. It would be really easy to feed of another person and I have done this before.
MS