Eye witness testimony Flashcards
- eye witness testimony is?
- provides? however?
- relies on? however? (3)
- Evidence given by witnesses to crime typically in form of verbal account or person identification
- crucial evidence, juries like eyewitnesses, data indicates they are often wrong in who they identify
- relies on accuracy of human memory however human memory is not perfect, not permanent, forgetfulness is factor of our reality
- eye witness testimony is?
- provides? however?
- Evidence given by witnesses to crime typically in form of verbal account or person identification
- crucial evidence, juries like eyewitnesses, data indicates they are often wrong in who they identify
- Perception & memory as evidence (4)
- Ebbinghouse’s 3 stages of memory
- Yerkes-Dodson
Encoding - acquisition of info (Yerkes-Dodson law) Storage- retention Retrieval- giving testimony Weapon Effect 1. acquire info 2. storage 3. retrieval - effect of physio arousal on learning; low levels, relaxed, bored=very little learning; high levels, stressful-learning impaired. Remember best somewhere in between
Process of memory (4)
Encoding(Yerkes-Dodson law)
Storage
Retrieval
Weapon Effect
Retention/Storage
- memory is?
- by? (3)
- Memory subject to external influences; details involved are forgotten quickly early on
- Discussion with other witnesses
- Exposure to media accounts
- Passage of time
Encoding/acquisition
- influences
- factors influencing encoding (4)
Effect of crime type on memory, Violent crimes may narrow victims focus: Draws attention to central details, Reducing peripheral detail reliability
Weapon may draw attention from other details
1. Event complexity & meaningfulness
2. Frequency & length of exposure
3. Witness’s expectations & prejudices
4. Stress
Retention/Storage
- memory is?
- by? (3)
- Memory subject to external influences
- Discussion with other witnesses
- Exposure to media accounts
- Passage of time
Retrieval
- influenced by (2)
Memory accuracy influenced by
Interview style
Use of recall aids
(e.g. photofit & identity parades)
Witness Accuracy Impediments - 5
- Disguise
- Alcohol or Drugs
- Interviewer interruption
- Cross-racial identification problems
- Own-race bias
Strength and reliability of evidence: (and their effects)
- reliable and strong factors (2)
- reliable and moderate factors (2)
- weak or non-influentail factors (2)
- E.g. adult vs child witness, use of disguise; Consistent effects on memory
- E.g. correlation between witness memory confidence
& accuracy, weapon focus; Show effects in some studies & not others - Witness gender, personality; Little or no effect on memory
Weapons effect
Visual attention by witnesses usually give more attention to the weapon vs person holding it so distracts focus; when weapon used recall poor
Alfred Binet
first psychologist to advocate for research into eye witness testimony, (leading questions impact on testimony)
experiment on eye witness testimony
staged mock assault in front of 141 students, did photo line up 7 weeks later, 60% misidentified, 2/3 picked innocent bystanders
Lipton 1970’s experiment
Showed film of shooting, didn’t tell them they’d be eye witnesses, questioned after 1 week, memory loss of 18% vs. those interviewed after film
Liz Loftus
said language can influence the retrieval of information
