Presentation on theme: "Social Psychology and the Law"— Presentation transcript:
1Social Psychology and the Law Chapter 16Social Psychology and the Law
2Social Psychology and the Law Studying the legal system helps psychologists see how behavior occurs in complex, personally relevant, and emotion-laden contests.
3Eyewitness TestimonyEyewitness identifications are frequently inaccurate.
4Eyewitness TestimonyThe three basic processes of acquisition, storage, and retrieval influence eyewitness memory, just as they influence all memory.
5Eyewitness TestimonyTwo groups of factors influence eyewitness identificationEstimator variablesconcern the eyewitness and the situationSystem variablesare under the direct control of the criminal justice or legal system.
6Eyewitness Testimony Viewing Opportunity The longer witnesses look and the more attention they are able to pay, the more accurate their identificationsHowever, witnesses are just as likely to think they can make an identification if they have witnessed an event under poor viewing conditions.
7Eyewitness Testimony Stress and Arousal Stress increases memory for the event itself but decreases memory for what preceded and followed the incident
8Eyewitness Testimony Weapon Focus Effect People tend to keep their eye on weapons because of their danger and noveltyThis distracts their attention from the robbers
9Eyewitness Testimony Own-Race Bias People are more accurate in identifying members of their own raceOwn-race bias decreases with experience with other groupsThus blacks are more accurate in identifying whites than vice versa.
10Eyewitness Testimony Retention Interval Accuracy drops with time rapidly at first, then levels off.
11Eyewitness Testimony Suggestive Questioning The way witnesses are questioned influences their memories of the event.Some questions are suggestive but not deliberately misleadingE.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” itOther questions are deliberately misleading, asking about nonexistent details.
12Eyewitness TestimonyThree hypotheses for how post-event information affects memoryover-writingforgettingsource monitoringPeople retain memories of both the event and any post-event information but cannot identify the source of the memoriesEvidence supports the latter.
13Eyewitness Testimony Lineup Biases The way lineups are conducted can have a tremendous effect on the accuracy of eyewitness identification.
14Eyewitness Testimony Show-ups Simultaneous lineups Sequential lineups asks witnesses to indicate whether or not a single witness is the perpetratorSimultaneous lineupsshow the witness several potential suspects at the same time.Sequential lineupsshow potential suspects one at a time
15Eyewitness TestimonySequential lineups allow the most careful attention to each person and the most careful decision-making and are most accurate.
16Eyewitness TestimonyAnother 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 witness’s initial description of the perpetrator.
17Eyewitness TestimonyInstructions 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.
18Eyewitness TestimonyThis research has affected U.S. Department of Justice guidelines for police to use when questioning eyewitnesses.
19Criminal Defendants Voluntary False Confessions. Coerced complaint false confessionswhen people are pressured to admit guilt but privately believe their own innocence.Coerced internalized false confessionswhen 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.
20Criminal Defendants Lie Detection Observers do not detect lies at much better than chance ratesDespite nonverbal leakageLaw enforcement professionals are generally not more accurateThere is no correlation between how well people believe they detect lies and how well they actually do
21Criminal 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 debatedadvocates claim 90% accuracy, while published research estimates 57-76% accuracy, not much better than chance (50%).
22Criminal DefendantsHow 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.
23Criminal Defendants Aversive racism theory People should suppress racist thoughts when race is salientRace may have an effect when people are unaware that it may have one.Race may have an effect when people’s 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.
24Criminal 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.
25JuriesJury SelectionThe voir dire process allows judges and lawyers to question prospective jurorsGoal 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 reasonsE.g., occupation or personality traits (but not race or gender)
26Juries Demographic factors are not always predictive of verdicts this is most likely when group membership is relevant to the case
27JuriesJurors who are high in authoritarianism are more likely to convict.“Death qualified” juries are more likely to convict.
28JuriesAccording to Hastie and Pennington’s 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 createdThe story that best fits the evidence determines the verdict chosen.
29Juries 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.
30Juries 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.
31Expert TestimonyPsychologists 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.
32Expert TestimonyExpert testimony that draws links between the research and the particular case has larger influence on jurors than research that just presents the research findings.