Criminal Psychology Flashcards
What is the background for Hall & Player?
In response to Dror’s research that fingerprint experts are affected by cognitive bias . They thought it was important to ascertain if the normal working practices employed by the metropolitan police fingerprint bureau introduce an emotional bias.
What is the aim to Hall & Player?
to test if context had an affect on fingerprint identification by fingerprint experts, and attempted to answer; does the written report of a crime, as routinely supplied with the fingerprint evidence, affect a fingerprint experts interpretation of a poor quality mark?/ Are the fingerprint experts emotionally affected by the circumstances of the case?
What is the method to Hall & Player?
-laboratory experiment
-task was artificially generated and participants depressingly allocated a condition out of two
-IV was weather the participant was allocated to the low-context or the high-context group
-DVs: read crime scene examination prior examining finger print \ weather participant considered the finger print to be identification, not an identification, insufficient, or insufficient detail to establish identity
What is the sample to Hall & Player?
-volunteer sampling
-group of fingerprint practitioners chosen to represent a wide variation of experience
-70 fingerprint experts working for metropolitan police fingerprint bureau
-low context group - 35 ppts
-high context groups- 35 ppts
What materials were used in Hall & Player?
-finger print impression from a known source
-volunteers right finger was inked and introduced to a price of paper
-then scanned into a computer and superimposed on a scanned image of a £50 note
-14 copies made and were compared for consistency
-allowed a fingerprint magnifying glass and a tussle comparator
What was the procedure to Hall & Player?
-asked to participate during work time for it to be naturalistic
-randomly asigned in groups of 8
-no time limit and were told to treat the experiment as an ordinary case
-low - context groups: 35 ppts were given an examination report referring to forgery “suspect entered premises and tried to pay for goods with a forged £50 note”
-high - context groups: 35 ppts were given a report referring to murder ‘suspect then fired two shots at victim before decamping’
-researcher stayed with each group at all times to answer any questions
-they were then asked to consider whether the mark was an identification, not an identification, insufficient, or insufficient detail to establish identity
-were then given a feedback sheet which asked weather or not they had referred to the crime scene examination and if they had they were asked if the report had effected their analysis and if so how?
What were the results to Hall & Player?
-57 of 70 ppts read crime scene examination prior to examining prints 30 were high context condition
-52% of 30 high context condition felt they were effected by report indicating that there is a relationship between type of context and the perceived effect on the experts
Identification; H=6 L=7
No identification; H=1 L=0
Insufficient; H=15 L=12
Insufficient to establish identity; H=13 L=16
What were the conclusions to Hall & Player?
-emotional context affects a fingerprint experts analysis but has no actual affect on their final decision
-severity of case affects the fingerprint experts analysis but does not have any affect on their final decision
