Social Psychology and the Law

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Chapter 16

• Social Psychology and the Law

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Social Psychology and the Law

• Studying the legal system helps psychologists see
  how behavior occurs in complex, personally
  relevant, and emotion-laden contests.

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Eyewitness Testimony

• Eyewitness identifications are frequently
  inaccurate.

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Eyewitness Testimony

• The three basic processes of acquisition,
  storage, and retrieval influence eyewitness
  memory, just as they influence all memory.

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Eyewitness Testimony

• Two groups of factors influence eyewitness
  identification
• Estimator variables
• concern the eyewitness and the situation
• System variables
• are under the direct control of the criminal
  justice or legal system.

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Eyewitness Testimony

• Viewing Opportunity
• The longer witnesses look and the more attention
  they are able to pay, the more accurate their
  identifications
• However, witnesses are just as likely to think
  they can make an identification if they have
  witnessed an event under poor viewing conditions.

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Eyewitness Testimony

• Stress and Arousal
• Stress increases memory for the event itself but
  decreases memory for what preceded and followed
  the incident

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Eyewitness Testimony

• Weapon Focus Effect
• People tend to keep their eye on weapons because
  of their danger and novelty
• This distracts their attention from the robbers

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Eyewitness Testimony

• Own-Race Bias
• People are more accurate in identifying members
  of their own race
• Own-race bias decreases with experience with
  other groups
• Thus blacks are more accurate in identifying
  whites than vice versa.

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Eyewitness Testimony

• Retention Interval
• Accuracy drops with time rapidly at first, then
  levels off.

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Eyewitness Testimony

• Suggestive Questioning
• The way witnesses are questioned influences their
  memories of the event.
• Some questions are suggestive but not
  deliberately misleading
• E.g. Loftus Palmer found that people said a car
  had been going faster in an accident if they
  asked about its speed when it smashed into the
  other car as opposed to hit it
• Other questions are deliberately misleading,
  asking about nonexistent details.

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Eyewitness Testimony

• Three hypotheses for how post-event information
  affects memory
• over-writing
• forgetting
• source monitoring
• People retain memories of both the event and any
  post-event information but cannot identify the
  source of the memories
• Evidence supports the latter.

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Eyewitness Testimony

• Lineup Biases
• The way lineups are conducted can have a
  tremendous effect on the accuracy of eyewitness
  identification.

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Eyewitness Testimony

• Show-ups
• asks witnesses to indicate whether or not a
  single witness is the perpetrator
• Simultaneous lineups
• show the witness several potential suspects at
  the same time.
• Sequential lineups
• show potential suspects one at a time

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Eyewitness Testimony

• Sequential lineups allow the most careful
  attention to each person and the most careful
  decision-making and are most accurate.

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Eyewitness Testimony

• Another aspect of lineups is choosing foils
  (people other than the suspect in the lineup).
• Identifications are most accurate when all of the
  foils look like the witnesss initial description
  of the perpetrator.

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Eyewitness Testimony

• Instructions given to eyewitnesses are also
  important.
• Identifications are most accurate when the
  witness is told that the suspect may or may not
  be in the lineup.

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Eyewitness Testimony

• This research has affected U.S. Department of
  Justice guidelines for police to use when
  questioning eyewitnesses.

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Criminal Defendants

• Voluntary False Confessions.
• Coerced complaint false confessions
• when people are pressured to admit guilt but
  privately believe their own innocence.
• Coerced internalized false confessions
• when people come to believe they committed crimes
  they did not commit.
• This may occur when the behavior seems plausible
  and when other people claim they are guilty.

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Criminal Defendants

• Lie Detection
• Observers do not detect lies at much better than
  chance rates
• Despite nonverbal leakage
• Law enforcement professionals are generally not
  more accurate
• There is no correlation between how well people
  believe they detect lies and how well they
  actually do

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Criminal Defendants

• Polygraph (lie detector) tests
• ask suspects to answer questions while hooked to
  a machine that records physiological responses.
• The control question test asks about the
  critical, as well as about unrelated,
  wrongdoings.
• The accuracy of polygraph tests is debated
• advocates claim 90 accuracy, while published
  research estimates 57-76 accuracy, not much
  better than chance (50).

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Criminal Defendants

• How do characteristics of defendants influence
  the decisions made by juries?
• Physically attractive defendants are less likely
  to be found guilty.
• Black defendants receive disproportionately
  harsher sentences than whites.
• This result is found in archival studies while
  the results of lab studies are inconsistent.

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Criminal Defendants

• Aversive racism theory
• People should suppress racist thoughts when race
  is salient
• Race may have an effect when people are unaware
  that it may have one.
• Race may have an effect when peoples behavior
  can be justified by factors other than race.
• According to this theory, jurors would be more
  likely to discriminate in trials where the race
  of the defendant is not made salient.

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Criminal Defendants

• Sommers and Ellsworth (2000, 2001)
• Participants read about a white or black
  defendant who slapped his girlfriend in public.
• Half read that the defendant said, You know
  better than to talk that way about a man in front
  of his friends. The other half read the same
  sentence with the words white man or black
  man.
• In the first condition (race not salient),
  white participants made harsher judgments against
  the black than against the white there was no
  difference in the race-salient condition.

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Juries

• Jury Selection
• The voir dire process allows judges and lawyers
  to question prospective jurors
• Goal is to assess the presence of biases that
  would interfere with their ability to render a
  fair judgment.
• Peremptory challenges allow attorneys to
  eliminate jurors for a number of reasons
• E.g., occupation or personality traits (but not
  race or gender)

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Juries

• Demographic factors are not always predictive of
  verdicts
• this is most likely when group membership is
  relevant to the case

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Juries

• Jurors who are high in authoritarianism are more
  likely to convict.
• Death qualified juries are more likely to
  convict.

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Juries

• According to Hastie and Penningtons story model
  of jury decision making, jurors use the evidence
  presented in trials to create stories about the
  events in question.
• Multiple competing stories may be created
• The story that best fits the evidence determines
  the verdict chosen.

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Juries

• Comprehension of Judicial Instructions
• Juries may have problems understanding and
  applying legal instructions.
• On-going research is looking for solutions, for
  example, rewriting instructions in more
  user-friendly language and allowing jurors to
  take notes.

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Juries

• Jury Deliberations
• Twelve-person juries are more representative and
  spend more time deliberating than six-person
  juries.
• Juries using a unanimous decision rule discuss
  the evidence longer and more thoroughly than
  juries using a majority decision rule.

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Expert Testimony

• Psychologists are increasingly asked to give
  expert testimony in court cases.
• Judges must consider the scientific reliability
  of the evidence, but may lack the necessary
  background to rule effectively.

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Expert Testimony

• Expert testimony that draws links between the
  research and the particular case has larger
  influence on jurors than research that just
  presents the research findings.