Hall & Player (Topic 2 crim)

Question 1

Background

Answer 1

Dror et al (2005) gave university research students either good quality, incomplete or poor quality fingerprints to study and low level or high level emotional stimuli.
Results showed students were affected by emotional context, this inferred with their decisions making them more likely to make misidentifications when analysing poor quality/ambiguous prints.

Question 2

Aim

Answer 2

To test the effect of context on fingerprint identification by fingerprint experts.

Question 3

Method

Answer 3

Lab experiment- but designed to be as life like as possible.
Took place during work time in typical fingerprint examination room.
Independent measures design.
Metropolitan police.

Question 4

IV

Answer 4

whether the ps were allocated low context or high context group

Question 5

DVs

Answer 5

whether the ps read the crime scene examination report prior to examining the fingerprint.
whether the ps could make an identification.
whether the ps would be confident to present the fingerprint as evidence in court.

Question 6

The fingerprint

Answer 6

A volunteer’s right forefinger was inked onto piece of paper, good quality clear mark, scanned on to computer and superimposed on scanned image of £50 note.
Mark was positioned so the background of note obscured majority of ridge detail.
Finger mark and corresponding set of fingerprint impressions were given to ps, asked to give their expert opinions as to whether there was a match.
Each ps was allowed access to a fingerprint magnifying glass and optical magnifying unit.

Question 7

Controls

Answer 7

Volunteers were randomly allocated groups and asked to treat experiment as they would a typical day, no time limit put in place.

Question 8

Low context group

Answer 8

35 ps
given report referring to allegation of forgery (victimless crime). Modus operandi stated a “suspect entered premises and tried to pay for goods with forged £50 note. Forgery was spotted by cashier, suspect then left”

Question 9

High context group

Answer 9

35 ps
Given report about an allegation of murder. Final wording on report read “Suspect then fired two shots at victim before decamping”

Question 10

Procedure- gathering data from ps

Answer 10

Ps completed a demographic information sheet detailing where they worked, how many years experience as an expert and whether they had presented evidence at court.
Experts then asked to consider whether mark was an identification/match or not or insufficient (not enough detail to undertake comparison) or insufficient detail to establish identity.
Also were asked to elaborate on their findings & complete feedback sheet asking whether they had referred to crime scene examination report, and if so what info they had read and whether they felt the info contained on report affected their analysis and if so, how.

Question 11

Results

Answer 11

81.4% indicated that they read crime scene report before examining prints.
52.6% of them were in high context group, 47.4% were in low context group.
52% of those who read high context scenario felt affected by info given on examination report.
only 6% felt affected by info in low context scenario group.

Question 12

Final decisions made by experts

Answer 12

Found to be similar regardless of emotional context.
Not statistically significant.
Only variation was whether they thought mark had insufficient detail to undertake comparison.
46% of experts in low context scenario stated they had some points in agreement, but not enough to individualise compared to 37% of experts given in high context.
17% of high context and 20% of low context were confident enough to present mark as positive identification to court ( not a significant difference)
Overall results showed the manipulated finger marks lay at the boundary of making a conclusive match confirming mark to be ambiguous.

Question 13

Conclusions

Answer 13

Although emotional context affects fingerprint expert’s analysis, it doesn’t have any effect on their final decisions.
Severity of a case effects analysis, but again does not effect final decisions.
Different crime type contexts do not significantly affect experts final decisions.
Details of a crime provided with finger marks is seen as unnecessary by experts.
Experts are adept at dealing with fingerprint analysis in non-emotional, detached manner.
There may be motivating factors and bias in collection and processing of forensic evidence.

Question 14

Evaluation: Usefulness

Answer 14

Emotional context of situation did not affect decision making of print analysis, evidence useful and reliable enough to be used in court. Despite positive results, bias still possible. External validity questioned. Expert evidence more reliable than non-expert evidence.

Question 15

Evaluation: Individual/ situational explanations

Answer 15

Findings support individual explanation.
Experts not influenced by situational factors such as high/low emotional context and regardless of case accurate decisions made by experts.
However non-experts are influenced by situational factors, misidentification can occur.

Question 16

Evaluation: Sampling bias

Answer 16

Ps were volunteer fingerprint experts, certain type of expert, possibly confident in their ability and less likely to be influenced by emotional context of a crime.
All worked for Metropolitan police, not representative of all police forces.
Lacks population validity.

Question 17

Ethical considerations

Answer 17

Ps were informed they were taking part in experiment, made aware their data remained anonymous and confidential, unique reference number used for each ps.
Stress and embarrassment risk if ps misidentified match and if peers found out.
Normal task they would usually do at work, low psychological harm.
Emotional state of scenarios may have caused some psychological harm in high emotional context. (Dror et al ps were emotionally affected)

Question 18

Usefulness

Answer 18

Identification of a match was not affected by emotional context of crime scene report, could be in less experienced departments.
To an extent we can assume findings can be generalised to other professionals working in fingerprint analysis. (reliable)
Results can be generalised to those who may need to make decision in emotional context when identifying DNA matches e.g hair, blood.
Despite positive results bias still possible, take caution.
Research has led to developing training programmes to reduce possible effects of cognitive bias in fingerprint examination.

Question 19

Ecological validity

Answer 19

Lacks ecological validity.
Ps knew it wasn’t a ‘live’ mark, knew it was an experiment (demand characteristics)
To create mundane realism, was done during working hours, hoped the experts would become involved and ‘forget’ it was experiment.
Told fingerprint was only piece of evidence being presented in the case-raises responsibility felt by experts(lack ecological validity)
As testing was on £50 note, plus details of crime scene given, implies suspect was holding money at time of crime, suggesting they’re responsible.
Dror et al-studying non experts- whole situation artificial for ps, not generalisable to circumstances of processing forensic evidence.

Question 20

Sampling bias

Answer 20

Used experts in fingerprint analysis field, more representative than Dror et al’s sample that was under representative of those working in forensics.
Of the 70 ps in the study, all worked for Metropolitan Fingerprint Bureau in London, well funded department, well trained.
12 of them were no longer active practitioners, results concerning fingerprint identification & emotional contexts cannot be generalised to all fingerprint experts in other police forces/countries or fields in forensics who also may encounter emotional contexts.
Effects of cognitive bias more pronounced amongst less well trained experts, further research likely required.

Question 21

Individual vs situational debate

Answer 21

Individual side supported.
Experts not influenced by situational factors e.g high or low emotional context, regardless of case accurate decisions made.
Non experts (Dror et al) are influenced by situational factors, misidentification can occur.

Question 22

Psychology as a science

Answer 22

Supports psych as a science, tested hypotheses and manipulated an IV.
E.g ps randomly allocated to conditions (low/high context) allowing them to test whether experts were emotionally affected by circumstances of case.

Question 23

Free will vs determinism

Answer 23

Dror supports determinism due to emotional contexts such as murder and personal attacks influencing decision-making.
However when analysis carried out on experts, able to exert free will and own judgement when deciding whether there was a fingerprint match.