The Psychology of Juries

Background

  • Early evidence of juries dates back to Egypt, 4000 years ago.
  • The concept of trial by jury of ordinary citizens originated in Athens.
    • Jurors were selected by lottery.
  • The idea spread across Europe and was introduced to Britain by the Normans.
  • Until 1670, juries could be fined or imprisoned for disagreeing with the judge's verdict.

Australia

  • Rules vary by state.
  • Juror eligibility:
    • Citizenship is required.
    • Must be at least 18 years of age.
    • Ex-convicts are excluded.
    • Certain professions are exempt, including senators, judges, MPs, clergy, barristers, solicitors, medical practitioners, members of the armed forces, and police officers.
  • Juries are used in Supreme Court or Intermediate court cases, while magistrates handle minor offenses without a jury.

Jury Functions

  • Main function: Apply the law to the evidence and render a verdict of guilt or innocence.
    • Utilize the wisdom of 12 individuals.
    • Act as the community conscience.
    • Protect against outdated laws.
  • Jury Nullification: Juries may ignore the law and render a verdict based on other criteria.
    • This may occur in cases where juries believe the law is unfair.

Characteristics of a Jury

  • Impartiality:
    • Lack of bias on the part of jurors.
    • Threats to impartiality: Pre-existing biases, prejudices, or attitudes, and negative pretrial publicity.
  • Representativeness:
    • Ensured through random selection from the community.
    • Affected by how the original panel is selected, the percentage of the panel that appears in court, who avoids being called, and who is disqualified.

Jury Selection

  • The court uses voter lists and phone directories to find eligible people for juries.
  • People are randomly drawn from the list and summoned for duty.
  • Pretrial gathering of potential jurors from which jurors are selected
  • Peremptory challenges: Removal of a limited number of prospective jurors without specifying reasons. The number of these challenges is limited.
  • Challenge for cause: Both parties have an unlimited right to challenge with “cause” – i.e., for a stated reason.
  • Jury Selection: The process of choosing and shaping the jury through the use of peremptory challenge and challenge with cause.
  • In the US, this is an extensive process and it is common in high profile cases to hire “Trial Consultants” who assist in selecting a jury that will be sympathetic to particular case.
  • In AU the use of trial consultants is almost unheard of due to very limited availability of peremptory challenge.
  • Demographic variables do not consistently predict juror verdicts (Hastie et al., 1983).
  • Evidence is a substantially more potent determinant of juror’s verdicts than the individual characteristics of jurors.
  • When the evidence is ambiguous, juror’s personalities and general attitudes have an effect
  • Scientific jury selection
    • Attempts to draw correlations between demographics and trial-relevant attitudes
    • Consultants conduct a survey in the jury population
    • If prospective juror fits an unfavorable profile, use a peremptory challenge to exclude
    • Controversial process
      • Favour: Picking jurors using science is more refined version than intuition. Problem is in the peremptory challenge
      • Oppose: Problem with representativeness of jury. Tips the scales of justice toward the wealthy.

Studying Jury Behaviour

  1. Post-trial interviews
  2. Archival records
  3. Simulation techniques.
  4. Field studies

1. Post-Trial Interviews

  • Not possible in many countries because jurors are forbidden by law from disclosing content of their deliberations
  • Post-trial interviews with jurors from the U.S. can provide a valuable data source
  • Limitations include:
    • Social desirability of responses
    • Inaccurate recall

2. Archival Records

  • Use records of trials (e.g., transcripts, police interviews)
  • Limitations include:
    • Inability to establish cause and effect
    • Limited in what questions can be asked by the information available for collection

3. Simulation Techniques

  • Mock jurors are presented with a simulated trial. They are asked to render a verdict or make other judgements
  • Independent variables can be manipulated
  • Limitations include:
    • Questionable generalisability to real life cases

4. Field Studies

  • Research is conducted within a real trial
  • Enables researchers to observe the process as it is occurring
  • High ecological validity
  • Limitations include:
    • Obtaining permission from the courts may be difficult
    • Variables of interest cannot be controlled
  • Given these differences we should be wary of body of research evidence based only on one system
  • Most research examines US jury system. Very little consideration of other countries including Australia

Reaching a Verdict

  • Stages involved in reaching a jury verdict:
    1. Listening to the evidence
    2. Disregarding inadmissible evidence
    3. Judge's instructions
    4. Juror decision-making
    5. Deliberations
    6. The final verdict

1. Listening to the Evidence

  • Two aids have been proposed for jurors while they listen to the evidence:
    • Note-taking
    • Asking questions
Note-Taking
  • Some judges may allow jurors to take notes while listening to the evidence
    • May help jurors by increasing memory and understanding of the evidence, and increasing attention
    • Research indicates note taking is generally a helpful aid for jurors (Horowitz & ForsterLee, 2001)
Asking Questions
  • Jurors cannot always comprehend the meaning of statistical evidence and scientific findings
  • Jurors may be allowed to ask witnesses questions via the Judge
    • Research found that while jurors’ questions are appropriate and promote clearer understanding, they do not help get to the truth (Penrod & Heuer, 1997)

2. Disregarding Inadmissible Evidence

  • During trials, lawyers or witnesses may make inadmissible statements that juries will be instructed to disregard
  • Jurors may not ignore evidence although they have been instructed to disregard it (Hans & Doob, 1976)
  • In fact, instructions to ignore inadmissible evidence can boomerang– adding to the impact of the testimony
  • Why is it difficult for jurors to ignore inadmissible evidence?
    • The instruction draws attention to the controversial evidence
    • Arouses reactance: The desire to assert one’s sense of freedom
    • Jurors want to reach the right decision, regardless of legal technicalities

3. Judge’s Instructions

  • Studies suggest that jurors do not remember, understand, or accurately apply judicial instructions (Lieberman & Sales, 1997)
  • Reforms for judges’ instructions have been proposed (e.g., rewriting instructions, providing a written copy to jurors)

4. Juror Decision-Making

  • How do individual jurors make their decisions?
    • Mathematical Models
    • Explanation Models
Mathematical Models
  • Views jury decision-making as a set of mental calculations
    • A mathematical weight is assigned to each piece of evidence (Hastie, 1993)
    • Research indicates jurors do not put a value to each piece of evidence (Ellsworth & Mauro, 1998)
Explanation Models
  • Suggests evidence is organized into a coherent whole
    • E.g., Story model: Involves imposing a story structure to the evidence for each verdict option
    • Research indicates this is more consistent with how jurors make their decisions (Pennington & Hastie, 1988)

5. Jury Deliberation

  • Leniency bias
    • The tendency for jury deliberation to produce a tilt toward acquittal
  • Group Polarisation: When individuals tend to become more extreme in their initial position following group discussion
    • Study: Juries were shown a re-enactment of an actual murder case and then given unlimited time to deliberate the case in a jury room
  • Minority Influence
    • Is not overly likely in jury situations
    • A minority that favours acquittal stands a better chance than one that favours conviction

6. The Final Verdict

  • Two-thirds Majority Scheme: The jury verdict is usually the alternative favoured by at least two-thirds of the jurors at the outset
  • As of 2007, majority verdicts (11 to 1) are accepted in NSW after the jury has attempted and failed to reach a unanimous verdict.
  • Hung jury: A jury that cannot reach a verdict

Predicting Verdicts

  • Research has been conducted assessing if certain variables can predict verdict
  • Common variables assessed:
    • Demographic
    • Personality
    • Attitudes
    • Defendant characteristics

Demographics

  • The relation between juror demographic characteristics to verdicts is small and inconsistent (Bonazzoli, 1998)
  • There may be an interaction between the demographics of the jury and demographics of defendant or the nature of the offence
  • Participants more likely to render guilty verdicts and longer sentences for “other race” defendants (Mitchell et al, 2005)
  • When defendants’ race is made salient, white juror racial bias toward a black defendant was reduced (Cohn et al., 2009)

Personality

  • Some personality dimensions have been suggested to predict verdict
  • E.g., Moderate link between an authoritarian personality and rendering a guilty verdict (Narby et al., 1993)
  • Some jurors are more persuasive than others (e.g., extroverts, male, tall) (Marcus et al., 2000)

Attitudes

  • Jurors willing to give the death penalty are more likely to render a guilty verdict than those opposed to the death penalty (Horowitz & Seguin, 1986)
  • Research on other attitudes or values is insufficient to reach definitive conclusions

Defendant Characteristics

  • Criminal history has been found to impact verdicts (Hans & Doob, 1976)
  • Less attractive defendants found to be guilty when jurors did not deliberate, however the attractive defendant was more likely to be found guilty when jury allowed to deliberate (Patry, 2008)
  • Similarity-latency hypothesis: Jurors who share characteristics with the defendant will be lenient.
  • However, there is also a Black-sheep effect: Similarity between defendant and mock jurors predicted leniency, except where evidence against defendant was very strong – in which case they became more severe.

Arguments Against Juries

  • Being trialed by one’s peers does not guarantee a fair trial
  • Juries are not always representative of community
  • Jury does not give reason for decision
  • Juries can be unpredictable – decisions may not be rational
  • Jury trials often result in mistrials or hung juries
  • Juries are expensive and slow
  • Juries sometimes do not understand or remember evidence
  • Too important a job to be left to amateurs!

Arguments For Juries

  • It is an important civic responsibility and jurors feel sense of responsibility
  • Decision of group of peers more acceptable to defendant than decision of one non-representative judge
  • Each jury brings a “fresh eye”
  • Jurors possess “common sense”
  • Juries, unlike judges, can deviate from letter of law if they feel it is appropriate to do so

Summary: Judge or Jury

  • Given the problems faced by juries, should judges become the decision makers?
  • Survey of real judges revealed that they would have returned same verdict as jury in 78% of cases (Kalven & Zeisel, 1966)
  • Most legal professionals and experts agree that we should retain juries – however it is clear that there is lots of scope for improving the decision-making ability of juries.