Legal Psychology

Gerhard Ohrband

ULIM University, Moldova

9th lecture

Eyewitness testimony

Course structure

Lectures: • 1. Introduction into Legal Psychology – Theories of crime • 2. Correctional treatment• 3. Victimology• 4. Police psychology• 5. Testimony assessment• 6. Criminal responsibility• 7. Judicial judgments• 8. Psychological assessment of families

Course structure

Seminars:9. Eyewitness testimony10. Jury decision-making11. Child abuse12. Prostitution13. Rape14. Tax evasion15. Stereotypes and prejudices in the law system

Content

• Eyewitness identification: cognitive aspects• Eyewitness Testimony• Enhancing the quality of eyewitness testimony:

expert witnesses• Suggestibility in people with intellectual

disabilities• Research in detail: the effect of confirmatory

feedback on the witnessing experience

Eyewitness identification: cognitive aspects

• Eyewitness accounts provide crucial evidence that may lead to the identification and arrest of a criminal suspect.   Eyewitness testimony also plays an important role in the trial process.  The verdicts returned by juries, it has been argued, are heavily influenced by eyewitness identification.  Although most laboratory studies and real world data indicate that eyewitnesses are most often correct in their identifications, mistaken identification does happen and has tragic consequences.  Psychological investigations are beginning to reveal the factors that can influence eyewitness accuracy.

Eyewitness accuracy

• As a result of human information processing limitations, a person may be mistakenly identified as a criminal suspect by an eyewitness. The crime location may have been too dark, or the encounter may have been too brief for the eyewitness to accurately perceive the perpetrator.

• In addition, people tend to overestimate the duration of brief events, while they underestimate the duration of prolonged events (Penrod, Loftus, & Winkler, 1982).

• Other psychological research has demonstrated that the presence of a weapon also reduces the accuracy of eyewitness accounts (Loftus, Loftus, & Messo, 1987). This "weapons focus effect" appears to be the result of the observer's attention being directed toward the weapon, thereby diverting attention away from situational aspects and the perpetrator (Kramer, Buckhout, & Eugenio, 1990).

Question Wording and Eyewitness Testimony

The study of Loftus & Palmer (1974):

Participants viewed films about a car

accident. They were then asked:

„About how fast were the cars going when

they [verb] into each other?“

The verb was either collided, bumped,

contacted, hit, or smashed.

The results showed that speed estimates depended on the verb given:___________________________________Verb condition: Speed (miles per hour)___________________________________Contacted: 31.8 Hit: 34.0Bumped: 38.1Collided: 39.3Smashed: 40.8___________________________________

Question Wording and Eyewitness Testimony

In a second experiment, participants were asked whether they saw broken glass; in the film, no broken glass was shown. The distribution of „Yes“ and „No“ responses was:__________________________________Verb condition Yes No__________________________________Control: 6 44Hit: 7 43Smashed: 16 34__________________________________

Question Wording and Eyewitness Testimony

The more a verb indicated speed, the higher were

the speed estimates, and the higher was the

likelihood that participants saw broken glass,

although no broken glass was presented in the film.

This finding clearly shows that the wording of a

question influences subsequent answers, an issue

also examined in survey research.

Question Wording and Eyewitness Testimony

Memory processes

• In addition to perceptual errors, eyewitness accuracy may be reduced by errors that occur within the memory process. Memory can be divided into three stages: encoding, storage, and retrieval. Errors may occurs at any of these stages. The acquisition of information is referred to as encoding by cognitive psychologists. According to the Yerkes-Dodson principle, information is encoded best when a person is moderately aroused. At this level of arousal, a person's attention is focused and information is acquired well. Extreme arousal, or stress, however, causes information to be lost or encoded inaccurately.

Storage

• At the second stage of memory, storage, acquired stimulus information is stored. However, both interference and decay can reduce the accuracy of stored information. Decay refers to the loss of stimulus information due to the passage of time. The amount of time that has lapsed between the witnessing of the crime and the subsequent questioning of the eyewitness can determine the amount of information that the eyewitness recalls (Lipton, 1977). Secondly, interference, which refers to the loss of old stimulus information due to interference caused by new stimulus information, can also reduce the accuracy of eyewitness accounts.

Storage

• Gorenstein and Ellsworth (1980) found that after viewing mugshots, the accuracy of eyewitnesses' ability to recognize faces viewed before the mugshots was reduced. Moreover, questions that eyewitnesses are asked after the crime have been found to interfere with information that eyewitnesses acquired during the crime.

• In one study, subjects were shown a film of an automobile accident and then asked a series of follow-up questions about the accident (Loftus, 1979). A misleading follow-up question contained information about a barn, which was actually not present in the film. One week later, 17% of subjects erroneously reported seeing a barn in the film. In effect, the misleading question incorporated new and inaccurate stimulus information in the memory store.

Retrieval

• Retrieval, the final stage in the memory process, involves the recall of information from the memory store. Yet, recall may be influenced by the types of questions that eyewitnesses are asked. One study found that language can influence the retrieval of stimulus information (Loftus & Palmer, 1974). In this study, subjects were shown a film of an automobile accident and then asked a series of follow-up questions. Participants who were asked how fast the cars were going when the cars "smashed", reported an average speed of 40.8 mph. However, participants who were asked how fast the cars were going when the cars "contacted" reported an average speed of 31.8 mph. Suggestive questioning procedures, therefore, should be eliminated as much as possible to minimize their effect on eyewitness accuracy. 

Retrieval

• Another retrieval phenomenon, known as unconscious transference, refers to the generation of memory that is related to an incident, but, is not relevant to the issue being considered. For example, a bank teller who has been robbed, may mistakenly identify a one of his regular customers as a suspect. This phenomenon was demonstrated by Robert Buckhout (1974) when he staged a mock assault in front of 141 unsuspecting college students. Seven weeks later, these students were asked to pick the perpetrator from a group of 6 photographs. Of the 60% who did not correctly identify the assailant, 2/3 incorrectly chose an innocent bystander who was at the crime scene.

Retrieval

• There are several other phenomenon that have been examined for their effect on eyewitness memory.  Some of these include exposure to misleading post event information, lighting conditions, stress, weapon  focus, individual differences, cross-race effects, exposure duration and more.  For further reading, I reccomend Mistaken Identification, The Eyewitness, Psychology and the Law (Cutler & Penrod, 1995) and Adult Eyewitness Testimony (1994).

Inverted U-shaped function that some claim relates stress and memory

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Hi

LowStress

Mem

ory

Acc

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Deffenbacher's original ideas about how memory and stress are related to each

other

  

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Hi

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Low

HiSimple

Complex

 

Interaction idea about how stress and memory might be related that is similiar to Easterbrook’s

(1959) cue-utilization hypothesis.

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Stress

Mem

ory

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Hi AttendedInformation

UnattendedInformation

The experiment by Kemp et al. (1997):

Some credit card companies issue credit cards

that include an ID photo of the credit card holder.

Are trained employees at a supermarket, who all

are informed about the nature of the study, able to

correctly recognize the face on the photo?

Face recognition on ID photos

Together with a credit-card company, Kemp et al. (1997) issued four different credit cards for each of 46 students.

The categories were:

Face recognition on ID photos

Unchanged appearance: Photo of the student, same attributes

Changed appearance: Student, changed attribute (e.g., no glasses)

Matched foil: Other individual, looked fairly similar in appearance

Unmatched foil: Other individual, same gender, but looked different

Dependent variable was the cashier‘s decision to accept or to reject the credit-card.

0102030405060708090

100

U-A C-A M-F U-F

Male

Female

% Accurate Decisions

Face recognition on ID photos

This experiment clearly demonstrated that face

recognition is not at all perfect.

This sheds doubt on the practice to post ID

photos on credit-cards or to check ID photos

before boarding a plane.

Face recognition on ID photos

Eyewitness testimony

• It is often argued that despite the limitations of human information processing, jurors overestimate the validity of eyewitness testimony because they are unaware of all the factors that can compromise an eyewitness' accuracy. For example, jurors may be unaware of the factors that can interfere with eyewitness perception, such as the weapons focus effect, or factors that interfere with memory storage, such as the effect of prior exposures on suspect identification (Cutler, Penrod, & Dexter, 1990).

Eyewitness testimony

• Previous research finding demonstrate that jurors overestimate the accuracy of eyewitnesses.  To illustrate this point, in one study mock jurors were presented with a case of an armed robbery that resulted in two deaths (Loftus, 1974). Eighteen percent of the mock jurors, who heard only circumstantial evidence, convicted the defendant. However, 72% of the mock jurors who heard eyewitness testimony in addition to circumstantial evidence convicted the defendant. Even when the eyewitness had 20/400 vision, 68% found the defendant guilty.

Eyewitness testimony

• In addition, jurors already have a difficult time weighing the strength of a positive identification because of procedural safeguards.  For example, if other eyewitness were unable to identify the defendant jurors will not be told about it (Wells & Lindsay, 1980).  Given this possible initial setback, one implication is that jurors should have the benefit of hearing an psychological expert evaluate the eyewitness identification for weakness.

Expert witnesses• Eyewitness identifications of course are not always accurate

due to the limitations of human perception and memory.  In consideration of these limitations, it would seem appropriate for psychologists who are experts in the area of perception and cognition to educate juries so that they can better evaluate eyewitness testimony. 

• Judges, however, often do not permit psychologists to testify during trial because they believe that the research findings are not beyond the scope of common knowledge already held by the jurors.  Presenting the expert testimony, it is argued, would not enhance a jury's ability to weigh the evidence, and might even interefere with the fact finding process which should be left solely to the jury.  Additionally, some judges, psychological experts and others believe that research findings are not well enough established to present to jurors as established facts.

Expert witnesses•     In a recent survey of psychological experts, who are familiar

with eyewitness identification issues, most respondents agreed that an experts primary responsibility is to educate the jury, and that "jurors are more competent with the aid of expert testimony than without" (Kassin, Ellsworth, & Smith, 1989).  Additionally, this study found an agreement rate of 80% among experts for the following topics: the working of questions, lineup instructions, misleading post-event information, the accuracy-confidence correlation, attitudes and expectations, exposure time, unconscious transference, showups, and the forgetting curve. The findings from this survey study are taken by many to indicate that there is a well established body of research in the area of eyewitness identification that experts could be called on to testify.  Indeed one legal requirement that the court has to evaluate when considering whether an expert should be allowed to testify is whether there is general agreement or acceptance of the testimony that the expert will present.

Expert witnesses

• Other psychology and the law experts, however, caution that laboratory research findings cannot be generalized in situ (Konecni & Ebbesen, 1986; McCloskey, Egeth, and McKenna, 1986). 

• One limitation of experimental research is that it is conducted in laboratory settings that are only approximations of real world settings. 

• Compared to laboratory investigations, archival research may be a better way to investigate the criminal justice system (Konecni & Ebbesen, 1986).

Gudjonsson Suggestibility Scale (GSS; Gudjonsson, 1997)

• The only validated instrument to assess interrogative suggestibility

• Frequently used in the assessment of whether people with intellectual disabilities have the capacity to testify in court

• Procedure: asking respondents to recall a short story, using leading questions and pressure to change their responses

• Using the GSS, people with intellectual disabilites appear highly suggestible, relative to the general population.

• Discussion: Why is that so?

Extracts of the GSS2

Extract

… they saw a small boy / going down a steep slope / on a bicycle / and calling for help. / Anna and John ran after the boy / and John caught hold of the bicycle / and brought it to a halt. / The boy appeared very frightened / but unhurt / … Anna and John recognized the boy / whose name was William.

Examples of leading questions

Did the boy on the bicycle pass a stop sign or traffic lights?

Did the boy drop the books he was carrying whilst riding the bicycle?

Was Anna worried that the boy might be injured?

Did John grab the boy’s arm or shoulder?

Literature• Adams, S. H. (1996, October). Statement anaysis: What do suspects’ words really reveal? FBI

Law Enforcement Bulletin, pp. 12-20.• Brandon, R., & Davies, C. (1973). Wrongful imprisonment. London: Allen & Unwin.• Brigham, J. C., & Malpass, R.S. (1985). The role of experience and contact in the recognition of

faces of own- and other-race persons. Journal of Social Issues, 41 (3), 139-156.• Brigham, J. C., & Wolfskeil, W. P. (1983). Opinions of attorneys and law enforcement personnel

on the accuracy of eyewitness identifications. Law and Human Behavior, 7, 337-349.• Buller, D. B., Burgoon, J. K., Buslig, A., & Roiger, J. (1996). Testing Interpersonal Deception

Theory: The language of interpersonal deception. Communication Theory, 6, 268-289.• Cutler, B. L., Penrod, S. D., & Dexter, H. R. (1989). The eyewitness, the expert psychologist, and

the jury. Law and Human Behavior, 13, 311-322.• DePaulo, B. M., Lindsay, J. J., Malone, B. E., Muhlenbruck, L, Charlton, K., & Cooper,. H. (2003).

Cues to deception. Psychological Bulletin, 129, 74-112.• Dulaney, E. F. (1982). Changes in language behavior as a function of veracity. Human

Communication Research, 9, 75-82.• Ekman, P. (1985/1992). Telling lies: Clues to deceit in the marketplace, politics, and marriage

(2nd ed.). New York: Norton.• Fox, S. G., & Walters, H. A. (1986). The impact of general versus specific expert testimony and

eyewitness confidence upon mock juror judgment. Law and Human Behavior, 10, 215-228.• Kastor, E. (1994, November 5). The worst fears, the worst reality: For parents, murder case

strikes at the heart of darkness. The Washington Post, p. A15.• Knapp, M. L., Hart, R. P., & Dennis, H. S. (1974). An exploration of deception as a

communication construct. Human Communication Research, 1, 15-29.

• Lindsay, R. C. L., Wells, G. L., & O’ Connor, F. J. (1989). Mock-juror belief of accurate and inaccurate eyewitnesses: A replication and extension. Law and Human Behavior, 13, 333-340.

• Loftus, E. F. (1979). Eyewitness testimony. Cambridge, MA: Harvard University Press.• Loftus, E. F., & Ketcham, K. (1991). Witness for the defense. New York: St. Martin’s Press.• Loftus, E.F., Loftus, G.R., & Messo, J. (1987). Some facts about “weapon focus”. Law and

Human Behavior, 11, 55-62.• Loftus, E.F., & Palmer, J. C. (1974). Reconstructions and automobile destructions: An example of

the interaction between language and memory. Journal of Verbal Learning and Verbal Behavior, 13, 585-589.

• Newman, M. L., Pennebaker, J. W., Berry, D. S., & Richards, J. M. (2003). Lying words: predicting deception from linguistic styles. Personality and Social Psychology Bulletin, 29, 665-675.

• Ohrband, G. & Römer, T. (2006). Achtung Vorurteile: zum Stereotype Rebound-Effekt • in der Personalauswahl. Hamburg: internet-publication.• Orne, M. T. (1979). The use and misuse of hypnosis in court. International Journal of Clinical and

Experimental Hypnosis, 27, 311-341.• Orne, M. T., Soskis, D. A., Dinges, D. F., & Orne, E. C. (1984). Hypnotically induced testimony.

In G. L. Wells & E. F. Loftus (Eds.), Eyewitness testimony: Psychological perspectives. New York: Cambridge University Press.

• Pennebaker, J. W., Francis, M. E., & Booth, R. J. (2001). Linguistic Inquiry and Work Count: LIWC 2001. Mahwah, NJ: Lawrence Erlbaum.

• Richards, J. M., & Gross, J. J. (1999). Composure at any cost? The cognitive consequences of emotion suppression. Personality and Social Psychology Bulletin, 25, 1033-1044.

• Richards, J. M., & Gross, J. J. (2000). Emotion regulation and memory: The cognitive costs of keeping one’ s cool. Journal of Personality and Social Psychology, 79, 410-424.

• Smith, M. C. (1983). Hypnotic memory enhancement of witnesses: Does it work? Psychological Bulletin, 94, 387-407.

• Rubin,. R., Peplau L. A., & Salovey, P. (1993). Psychology. Boston: Houghton Mifflin.

• Vrij, A. (2000). Detecting lies and deceit: The psychology of lying and the implications for professional practice. Chichester, UK: Wiley.

• Wells, G. L., Olson, E. A., & Charman, S. D. (2003). Distorted retrospective eyewitness reports as functions of feedback and delay. Journal of Experimental Psychology: Applied, 9 (1), 42-52.

• Wrightsman, L. S. (1987). Psychology and the legal system. Pacific Grove, CA: Brooks/Cole.

Internet resources

• http://eyewitnessconsortium.utep.edu

• http://www-psy.ucsd.edu/%7eeebbesen/prejvprob.html

Eyewitness Memory Research: Probative v. Prejudicial Value

• http://psy.ucsd.edu/~hflowe/eyeintro.htm

Eyewitness Identification Issues in Psychology