BHS 499-07 Memory and Amnesia

1. BHS 499-07Memory and Amnesia Memory and the Law

2. 5 Ways Memory Affects the Law • Accuracy of eyewitness testimony • Confidence of witnesses in their memories • Cognitive interviews that are most effective at aiding memory • Identification of perpetrators from lineups • Effects of memory processes on juries

3. Wording Effects • During questioning of witnesses, wording affects the answers. • “How fast were cars going when they _____ each other? • Choices were smashed, collided, bumped, hit, contacted • Next, “did you see any broken glass?” – 7% • Estimated speed – 40.8 with smashed & 16% saw glass, but 31.8 with contacted.

4. Misleading Postevent Info • When people are given misleading info after an event, it affects their memory for the event itself. • Consistent condition – yield sign was in video • Misleading condition – stop sign not in video • Control condition – no sign mentioned • Later given test -- 70% correct in consistent condition, 43% in misleading, 63% in neutral condition, with worse results after delay.

5. Theories • People who tell lies come to believe they are true later – a form of this effect. • Trace replacement theory – post info rewrites original info. • Coeexistence theory – both versions remain in memory but the misleading info is more recent so more accessible. • With warning, disregarded wrong info more.

6. More Theories • Response bias theory – guessing biases on the test account for the various %. • Tested using a new/old comparison without the misleading info as a response choice. • Source monitoring theory – people forget the source of the misleading info, especially during reflective tasks. • Impact depends on the source of the info.

7. Arousal Influences • Emotion affects memory in complex ways. • Yerkes-Dodson Law – bystanders more likely to remember than victims. • U-shaped curve because optimum arousal level. • Easterbrook Hypothesis – peripheral details weak, central details improved.

8. Arousal Influences (Cont.) • Weapon focus effect – increased memory for the weapon, decreased memory for everything else. • Occurs even when the weapon is not used.

9. John Dean’s Memory • John Dean’s memory of Watergate conversations was later compared to Nixon’s audio tapes for accuracy. • Dean was hardly ever right. • Dean wasn’t deliberately lying. • Important points were corroborated. • Self-centered bias. • Thoughts were incorporated into recalled conversations.

10. Eyewitness Confidence • Is a memory that a witness is unsure about less likely to be accurate? • Metamemory shows .41 correlation between accuracy and confidence (excluding those who identified no one in the lineup). • Confidence increases with post-ID feedback on accuracy. • Telling a witness that others made the same choice increases confidence.

11. Confidence (Cont.) • The more times a person is asked the same questions, the greater the confidence in the answers. • Judges and juries are sway by confidence. • External motivation (reward) for remembering increases confidence. • When people try harder, difficulty of recall cannot be used to assess accuracy.

12. Cognitive Interviews • Methods of gathering info have been developed to improve accuracy and prevent distortion. • First, attempt to reinstate the original context (internal and external) by having the person imagine or visit the scene. • Second, report partial info, whatever comes to mind, even if insignificant.

13. Interview (Cont.) • Third, report components of an event in a variety of orders, starting at different points. • Fourth, report the info from different perspectives. • Fifth, don’t interrupt. • Technique takes time but boosts recall up to 50% without increasing false info.

14. Eyewitness ID • Two kinds of errors: • Failing to ID a perpetrator • Mistakenly identifying an innocent person • Mugshots – if people see a set of faces and the real perpetrator is not among them, they may ID someone else. • This commitment impairs the ability to later ID the correct person, but just looking does not.

15. Lineups • Relative judgment principle – people not only compare the people to their memory but to others in lineup. • If others do not resemble the perp the one who comes closest may be picked. • Lineup similarity – the physical resemblance of others in the lineup matters. Fillers must fit the description.

16. Lineups (Cont.) • Instructions should include a statement that the correct person might not be in the lineup. • Otherwise pressure to select someone, anyone. • Errors more likely with a simultaneous lineup than a sequential one. • Forces a comparison with memory not others.

17. Lineups (Cont.) • Unconscious transference – an innocent bystander is identified as the perpetrator. • Memory bleeding explanation -- a person remembers seeing the person but becomes confused. • Source monitoring explanation – remembers the person but not the context.

18. Juries • Information order – juries try to construct info into a narrative. • To assess the impact of order two techniques are used: • Ask people to make decisions as they go along – shows recency effect. • Ask people to make decisions at the end, after all info has been given – primacy effect unless also given background info at start.

19. Inadmissible Evidence • Asking a jury to ignore inadmissible evidence is a directed forgetting request. • People are fairly efficient at doing this. • Juror’s memory for the inadmissible info is poorer than for the admissible info but it clearly has an impact on judgments. • Source info may be lost with forgetting.

20. Inadmissible Evidence • The more accurate jurors believe the inadmissible evidence to be, the more likely it will affect judgments. • Inadmissible evidence has a weaker impact during juror discussions because it can be identified and set aside. • Some inadmissible evidence comes from jurors themselves (their thoughts).

21. Children’s Testimony • It used to be thought that children did not or could not tell lies. • Now we know children can and do lie, even very young children. • Effective prosecution of child abuse cases requires child testimony. • Special procedures used – shields, suspension of hearsay rules, mandated videotaping of interviews.

22. Children as Participants • Is memory different when children are participants in an event, not bystanders? • Pairs of 4 & 7 yo kids in a trailer playing games, one playing and one observing • Open-ended versus specific questions, some misleading • 10 days later – older kids more accurate than younger, but no differences between observers & participants or suggestibility of abuse.

23. Pediatric Visit Study • 5 & 7 yo girls on a pediatric visit • Half had a scoliosis exam, half a genital exam • Tested at 1 & 4 weeks later • Older children more accurate about all questions, but no age differences for the misleading abuse questions. • More omission errors. • While not easily misled there were a lot of inaccurate answers to abuse-related questions.

24. Ornstein’s Studies • Significant age differences in children’s immediate and delayed recall. • 3 yo gave little open-ended info • As the delay increased considerable forgetting among the younger children. • Children laughed at the silly or strange questions asked.

25. Interviewing Techniques • Techniques that ask children to imagine things that may not have occurred or think about fictional events distort memory. • Use of peer pressure or authority affects memory. • Selectively reinforcing certain aspects of testimony introduces distortions. • Repeated interviews introduce distortions.

26. Repeated Questioning • Repeating misinformation across many questioning sessions results in impaired memory. • When misinformation is repeated eventually it is accepted by the child and becomes part of the child’s narrative.

27. Stereotype Induction • An attempt by the interviewer to transmit a negative characterization of a suspect. • Telling the child that the suspect “does bad things” or “tries to scare children.” • Some children incorporate this info into their answers.

28. Emotional Tone of Interview • Setting a warm and supportive tone encourages children to resist intimidation and counter false suggestions. • Some “supportive” environments may include subtle bribes, threats or rewards. • “We know something bad happened” • “You’ll feel better once you tell.” • This kind of support makes children more likely to fabricate statements.

29. Confirmatory Bias • A neutral or unbiased interviewer who inadvertently uses a biased technique is less problematic than a biased one. • Confirmatory bias – seeking evidence in support of a single hypothesis instead of testing alternatives. • Results in use of suggestive techniques that can distort memory.

30. Strength of Children’s Memories • While children’s memories can be changed by suggestive interviewing, children often show resistance to bias. • Children are not necessarily incorrect about everything – some facts will be correctly remembered. • Likelihood of disclosure is unrelated to threats made to children.