KHA312 Lecture Notes - Lecture 9: In-Group Favoritism, Confirmation Bias, Confounding
Psychology and law week 9: Juror decision making
Why are we interested?
- Central role of jury in criminal justice system
oDemocratic system
- How they process information
- What conditions facilitate good vs bad decision
- Essential to the process of justice
- Jurors: finders of facts
oMaking a decisions about the guilt or innocence, this falls on the juror
oEvaluate the arguments put forward by prosecution
oIs one plausible enough
- Conscience of community:
oJury nullification
oEquity
oEven play a role in saying that yes they are guilty, but the conditions
make it different
oAct to change the laws and processes
- Rests with groups of people with no particular expertise
oLay people making important decisions, under uncomfortable
conditions
Difficult decisions
Complex and ambiguous evidence
No training in critical analysis
oControversial decisions:
Reach decisions that raise questions
How did they arrive at this verdict
Eg. Liebeck and McDonalds and the hot coffee case
Paying large amounts of money out
Damages being covered by a third party
O. J. Simpson: can a black man have a fair trial
George Zimmerman:
Lived in gated community in Florida
oGroup and social processes
Effect on decision making
Methods: how do we study juror decision-making
- Investigating jury vs. juror decision making
- Why look at the individual
oIsolating basic cognitive processes
Avoid interactions between variables and individuals
So they cant have group discussion and social conformity
oLogistic/methodological concerns
Time, space, statistical power
Need a number of groups of jurors
Need a certain number of jurors
Difficult to do jury studies
oIndividual juror verdict best predictor of post deliberation
find more resources at oneclass.com
find more resources at oneclass.com
In most cases
Around 90% of cases
What individuals think provides a reasonable prediction of the
group
Can still get useful indication by focusing on individuals
- Non-experimental methods:
oLimited
Cannot do systematically
Thorough court law
Jurors have to deliberate in private
Therefore cannot watch, or question
oPost event questionnaires:
After deliberation
Asking about the processes
Influenced by social variables
Self reported measures
Unreliable
Don’t have internal access to cognitive processes that
effected decision making
Jurors might not want to be open about a number of things
Won’t be honest about certain aspects of the process
Even if they want to be honest, this might not be the case
Memory is flawed
Wont eb able to remember everything
Memory and reporting will be influenced by social
desirability
oPresent a unified front
oThat justice was executed
- Experimental methods:
oOvercoming the issues of non-experimental methods
oMock juror simulation:
Brief, written testimony
Audio, videos
With experimental manipulation
Jurors assess testimonial credibility, defendant
culpability, and deliver verdict
Guilty, not guilty
Usually categorical measure to match real life cases
Additionally rating scales will be used
oHow likely is it that they are guilty
oInsensitive measure
Based on the limit amount of information
it is impossible to be sure beyond
reasonable doubt
Simple methods:
2 + version of text, only varying in one variable
oeg race
find more resources at oneclass.com
find more resources at oneclass.com
between subjects design
link effects to variable of interest
simple effects vs. interactions
Building up the complexity of the experimental
Expanding basic effects to become more complicated
Pros of simple experiments:
oGood controls
Cons:
oDifficulties with realism
oMaterials are much simpler and less complex
Instructions too
the cases that make it to court are the
complex, messy cases
cannot mirror this complexity in
experimental materials
oInstructions given to jurors in real life is
complex
oJuror motivation
Undergraduates used
No bad consequences
Not generalizing to the high stakes
environment of real juries
oOnly looking at one juror
Don’t understand social processes in
juries
oNo deliberation
A final note on generality: generality and ecological
validity
Realism does not guarantee generality
oSomething that looks realistic, but the control
over it is weak
Replication and generalizing is weak
oThe role of theory
In order to generalize our findings from
lab
oDemonstrate then replicate
oIn the limited research, undergraduate students
don’t differ much to broader populations
oCompromise between level of control vs.
generalizing
How do jurors (not juries) make decisions?
- How do jurors evaluate evidence:
oStrength of evidence is primary basis for juror verdicts
oTypes of evidence that jurors like:
Eyewitness evidence but;
find more resources at oneclass.com
find more resources at oneclass.com
Document Summary
Psychology and law week 9: juror decision making. Central role of jury in criminal justice system: democratic system. What conditions facilitate good vs bad decision. Jurors: finders of facts: making a decisions about the guilt or innocence, this falls on the juror, evaluate the arguments put forward by prosecution, is one plausible enough. Conscience of community: jury nullification, equity, even play a role in saying that yes they are guilty, but the conditions make it different, act to change the laws and processes. Rests with groups of people with no particular expertise: lay people making important decisions, under uncomfortable conditions. No training in critical analysis: controversial decisions: How did they arrive at this verdict. Liebeck and mcdonalds and the hot coffee case. Damages being covered by a third party. O. j. simpson: can a black man have a fair trial. Lived in gated community in florida: group and social processes. Why look at the individual: isolating basic cognitive processes.
