Flashcards in 2 Eyewitness Testimony Deck (52):
How is eyewitness evidence important in an investigation?
Police are more likely to be successful to solve the case when an eyewitness is present.
What is the most common factor leading to wrongful convinctions?
What does extreme stress do to encoding (memory)?
Causes the person to encode incompletely or inaccuractely.
How do different expectancies play a role in memory?
Expectations can influence how memories are encoded. We generally have a tendency to see what we expect to see.
Memory fades as __________ ___________ increases. (storage)
How can the information be affected after the event?
1. Post-event information can alter memories.
2. Post-event information that confirms ones beliefs.
3. Viewing photographs can impair the ability to recognize.
What can influence incorrect retrieval?
1. Wording of a question
2. Unconscious transference
- One may pick from a lineup someone that they've seen before
but who is not the actual criminal.
What are the two types of recall memory?
Recall Memory - Report details of a previously witnessed event
Recognition Memory - Reporting whether what is currently being
seen/heard is the same as the previous.
What is an estimator variable?
Variables that affect the accuracy of eyewitness identifications, but cannot be controlled by the criminal justice system.
What are the six estimator variables?
2. Presence of Weapon
3. Attention (Perception)
4. Cross-race effect (Perception)
5. Time Lapsed
6. Lighting conditions
What is the yerkes-dodson law?
There is an empirical relationship between arousal and level of performance. When arousal is too high, performance decreases.
What is change blindness?
Failure to detect changes in the environment.
What is weapon-focus effect?
The concentration of witness attention on a weapon which means they pay less attention to other parts of the crime.
What is the cross race bias?
The tendency for people of one race to have difficulty recognizing differences in other races.
What are the two reasons the cross race effect occur?
1. Cognitive - We encode characteristics that we typically look for
in our own race.
2. Social - We see people in our own group as unique and people in
our out-group as more similar to eachother.
What are the six system variables used by police officers in eyewitness identification?
- Lineup Presentation
Why is simultaneous presentation of suspects a bad thing?
It forces witnesses to use process of elimination and "relative judgement."(Which looks MOST like the perpetrator)
Why is sequential presentation better for suspect lineup?
Forces witnesses to use "absolute judgement."
Which type of photo lineup reduces false positives (but not necessarily improves true-positives)?
What are some factors that affect photo presentation?
- All pictures must be similar (no outstandingly different photo)
- Legal right to have a defence attorney present so there are no
cues to witnesses to who the suspect is.
What are some misleading statements police officers might say to put pressure on the witness?
"We have someone in custody. We hope you can help identify him"
"Do your best"
"Take your time. It's really important to catch this guy."
What does suggestion by commission mean?
Pressure the eyewitness to make an identification.
What does suggestion by omission mean?
Failure to give the eyewitness instruction that the actual culprit may not be in the lineup.
What are some ways that a police officer could give confirming feedback?
- May congratulate the witness
- Tell the witness he/she picked the right person
- Tell the witness they did a good job
What are some traits of confidence in regards to eyewitness testimony?
- Confident witnesses are persuasive with jurors
- Confidence can be manipulated
- Confidence increases over time & successive identifications
Why do jurors overestimate accuracy?
- They have a baseline expectation that eyewitnesses are accurate.
- Jurors assume the eyewitnesses testimony is a reflection of
their memory quality.
- Jurors over-rely on an eyewitness's confidence.
What are three ways police officers may impede the interview process?
- Interrupt witnesses during free recall
- Asking questions not relevant
- Asking short specific questions that may not get at critical info
What could happen if police officers impede the interview process?
May lead to a misinformation effect.
What is an open ended recall/ free narrative?
Witnesses are asking to recount what they witnessed without being prompted.
What is a direct question recall?
Witnesses are asked specific questions about the event.
What is the misinformation effect?
Occurs whena witness is provided with inaccurate information about an event after it is witnessed and incorporated the 'misinformation' in later recall.
Why should somebody who doesn't know the suspect make the photolineup?
Because the eyewitness can pick up on nonverbal cues of investigator and alter behavior.
What are three important instructions upon viewing?
- Eyewitnesses should be told suspect might not be in the lineup.
- They should not feel like the make an ID
- The administrator should be blind
By how much did instructions on eyewitness viewing reduce the rate of mistaken ID's?
By 42% and did not decrease the rate of correct ones.
What tactics should be used in sequential presentation of lineups to make them more accurate?
- Suspect should not stand out
- Mock witnesses can be used to test lineups for bias's
- Non-suspects should be selected based on their resemblance
to the description provided by the witness.
What is important in obtaining confidence statements?
- Statement should be taken from eyewitness at time of ID
- Should be taken prior to any feedback from investigator
When psychologists are called for expert testimonys, why are judges reluctant to permit the expert testimony? (4)
1. Because they believe the research isn't established
2. Experts cannot offer more than common knowledge
3. This would open the gates to conflicting testimony
4. Might lead jurors to give insufficient weight to eyewitnesses
What is cross-examination?
When attorneys of the other party question the eyewitnesses
What are factors that effect eyewitnesses in cross examination?
- Knowledge of factors
- Because lawyers lack the knowledge of eyewitness memory, they
may ask the wrong questions.
- Judges must know the factors that influence accuracy eyewitness
What are the problems with judicial instruction?
- Judges educate jurors about relevant factors.
- Research shows jurors have difficulty understanding and
- Judges will not always oblige defence requests for in
What are all of the safeguards in eyewitness testimony?
- Double blind procedure
- Instructions on viewing
- Sequential Presentation of lineups
- Obtaining confidence statements
- Judicial Instructions
What are mistkane ID's like in the states? (& compensation?)
- 29 states compensate for the wrongly imprisoned
- About 1/3 of people wrongly convicted have not been
What is the innocence project?
- Recommend that all states exonerate people immediately after
release with a sum of recovery for each year of wrongful
- Recommended $50,000 per year of wrongful incarceration.
Why does children eyewitness differ from adults?
- Provide less information overall
- Less accurate
What difficulties do children experience with eyewitness testimony?
- In general, the same difficulties as adults
- Find it difficult to indicate the perpetrator is not in the lineup
- Likely to misidentify the suspect
- Children are more suggestible
At what age to children have difficulties distinguishing real vs. imaginary events?
Six and under.
How do jurors perceive child witnesses?
- Generally viewed as less credible
In what cases are younger victims perceived as more credible?
- Child sexual abuse cases.
- More credible because they lack the sexual knowledge to
fabricate such an allegation.
What does the criminal code of Canada and the Canada evidence say about children?
Protect children and other vulnerable persons from sexual exploitation, violence, abuse and neglect, and to provide testimonial aids for vulnerable victims.
What are option for children who fear appearing in open court?
- CCTV/ Video
- Screen used to block view of perpetrator
Why is it a problem for children to use CCTV and screening devices?
- Children may be less convincing to jury