RUNNING HEAD: Eyewitness Testimony
Eyewitness Testimony
Mark Maldonado
Grantham University
PS280 Psychology and the law
Eyewitness Testimony 2
Eyewitness testimony can create a number of problems for police and prosecutors. Some eyewitness’s do make mistakes on identifying someone and causes that person to be wrongfully convicted. It has happened time and time again. There is an organization called the Innocence
Project that stated 75% of the 218 people exonerated on the basis of DNA were mistakenly identified. Cognitive psychologists believe that under stressful situations a person can encode the information incompletely or inaccurately (Deffenbacher, Bornstein, Penrod, &McGorty, 2004).
In a military study on highly stressful interrogations (Morgan et al. 2004) they placed 500 military members in a mock prisoner of war camp. After 48 hours of being deprived of food and sleep deprivation they were interrogated. Half of them were threatened with physical harm and the other half was not. After one day they were asked to identify their interrogator’s from an eight picture line-up. Among those who were under moderate stress (not threatened with physical harm), 76% were right. But only 34% of those that WERE threatened with physical harm (high stress) were correct. There are three phases of the memory process: Encoding, Storage, and retrieval. Psychologists believe that errors can occur at any of these three phases. Psychologists state that even though our perceptual abilities are good (Penrod, Loftus, & Wrinkler, 1982) that we will make errors.
We tend to over or underestimate criminal’s height, weight etc. we overestimate how long or short the duration of the crime was.
Psychologists also stated that the longer it has been since the time occurred until the time we are asked to remember, the more memory loss we will have for faces (Deffenbacher, Bornstein,
McGorty & Penrod, 2008). During the storage phase, activities that eyewitnesses carryout or
Eyewitness Testimony 3
information they learn after an event, called postevent information, can alter their memory of the event. Loftus and Palmer did a study because they believed that eyewitness testimony can be unreliable and influenced by misleading questions (simplypsychology.org, Loftus and palmer (1974). To test their hypothesis they aimed to show that leading questions could distort eyewitness testimony accounts and so have a confabulating effect, as the account would become distorted by cues provided in the question. Forty-five American students formed an opportunity sample. This was a laboratory experiment with five conditions, only one of which was experienced by each participant (an independent measures design).
Forty-five American students were shown slides of a car accident involving a number of cars and asked to describe what had happened as if they were eyewitnesses. They were then asked specific questions about how fast were the cars going when they hit/smashed/collided/bumped/contacted each other.
The estimated speed was affected by the verb used. The verb implied information about the speed, which systematically affected the participants’ memory of the accident. Participants who were asked the “smashed” question thought the cars were going faster than those who were asked the “hit” question. The participants in the “smashed” condition reported the highest speeds, followed by “collided”, “bumped”, “hit”, and “contacted” in descending order (Loftus and Palmer (1974) study. Psychologists can provide much research and case studies on eyewitness testimony being unreliable. They have come to the conclusion that many factors can cause eyewitnesse’s to have trouble remembering events as they occurred, and identifying individuals accurately.
Eyewitness Testimony 3
Work Cited
Deffenbacher, Bornstein, Penrod & McGorty (2008). Retrieved on 6-16-2013 from Wrightsmans Psychology and the legal system (chapter 5 pg. 117).
McLeod, S.A. (2010). Loftus and Palmer – simply psychology retrieved on 6-16-2013 from http://www.simplypsychology.org/loftus-palmer.html.
Morgan et al. 2004. Retrieved 6-16-2013 from Wrightsmans Psychology and the legal system (chapter 5 pg. 117).
Penrod, Loftus & Wrinkler (1982) . Retrieved 6-16-2013 from Wrightsmans Psychology and the legal system (chapter 5 pg. 116).
Cited: Deffenbacher, Bornstein, Penrod & McGorty (2008). Retrieved on 6-16-2013 from Wrightsmans Psychology and the legal system (chapter 5 pg. 117). McLeod, S.A. (2010). Loftus and Palmer – simply psychology retrieved on 6-16-2013 from http://www.simplypsychology.org/loftus-palmer.html. Morgan et al. 2004. Retrieved 6-16-2013 from Wrightsmans Psychology and the legal system (chapter 5 pg. 117). Penrod, Loftus & Wrinkler (1982) . Retrieved 6-16-2013 from Wrightsmans Psychology and the legal system (chapter 5 pg. 116).