lesson 7: eye witness testimony

Question 1

What is eyewitness testimony (EWT)

Answer 1

individual witnesses a crime called ‘eye witness’, evidence given by a witness, form of a personal identification or verbal account

memory= not always accurate, problems on memory process: encoding, storage, retrieval

inaccurate= serious effect, wrong conviction

Question 2

Reasons why EWT can be unreliable
ANXIETY

Answer 2

witnessing a crime= high level of anxiety, effect encoding stage of memory process
violent crimes= high levels of anxiety

Question 3

Loftus, The Yerkes Dodson Law

Answer 3

performance= related to arousal (anxiety)
low arousal= low performance
increasing arousal= increasing performance
too much arousal becomes stress= anxiety, decreases performance

Question 4

Johnson & Scot, 1967, Weapon Focus Phenomenon
PROCEDURE

Answer 4

aim, if anxiety effects EWT
2 different situations:
1, overheard low key conversation about equipment failure, person came out holding a pen with grease on hands
2, overheard hostile, heated discussion in lab, after= sound of breaking glass & crashing chairs, man came out with paper knife covered in blood

Question 5

Johnson & Scot, 1967, Weapon Focus Phenomenon
FINDINGS

Answer 5

group with pen= 49% accurate at identifying person
group with knife= 33% accurate
known as weapon focus, distracts them from other details, anxiety decreases attention, worsening EWT

Question 6

Johnson & Scot, 1967, Weapon Focus Phenomenon
EVALUATION, STRENGTHS

Answer 6

+evidence to support
Loftus and Burns, Pp shown violent or non-violent short film crime
Pp who saw violent= less accurate recalling crime
anxiety= less accurate recall

+labatory
control extraneous variables
change in dependent variable due to change in independent
differences in accuracy of recall is because of change in scenario, high or low anxiety

Question 7

Johnson & Scot, 1967, Weapon Focus Phenomenon
EVALUATION, LIMITATIONS

Answer 7

• ecological validity
  not real life
  aware in experiment= not same response
  supported by different findings during real life events eg Yuille and Cutshall
• unethical
  Pp= deceived, upset by seeing bloody knife, break guidelines of minimising pain & stress
  psychologists= duty of care to protect Pp from harm

Question 8

Yuille and Cutshall, 1986, A real life event

Answer 8

how reliable memory is in real life setting
interviewed 13 witnesses to shooting in Canada with owner of a store
some closer than others
closest= most detail
misleading questions= no effect
impressively accurate accounts several months later
real life= accurate EWT

Question 9

Yuille and Cutshall, 1986, A real life event
EVALUATION, STRENGTHS

Answer 9

+ supportive research
Christianson and Hubinette questioned 110 witnesses, total witnessed 22 real life bank robberies
victims= more accurate than onlookers
event in real life= accurate recall

+ high ecological validity
real life shooting
real event memory= highly reliable

Question 10

Yuille and Cutshall, 1986, A real life event
EVALUATION, LIMITATIONS

Answer 10

• Canada
  can’t generalise to people not from Canada
• Natural experiment
  little control on variables
  several extraneous variables effecting result eg an eye witness could be a policeman, trained to remember details