Collection & Processing of Forensic Evidence (Bio)

Question 1

Charlton’s research into whether the apparent presence of emotions in FP examination would influence the analysis (study)

Answer 1

Qualitative approach using a semi structured interview

13 FP analysists

“How did you feel about succeeding in matching the prints?”

Question 2

What 5 themes did Charlton find amongst the experts

Answer 2

Reward of job satisfaction

Satisfaction associated with working on long-running cases

Satisfaction associated with catching criminals

Need for closure

Emotions linked to finding identification matches

Question 3

Bottom up processing in fingerprint analysis

Answer 3

Purely data driven

The specific details of the print informs the perception process

Question 4

Top down processing in fingerprint analysis

Answer 4

Analysis starts from a broader picture (context informs the perception process)

Question 5

Motivating Factors: Emotional Motivation

Answer 5

Individualistic

Charlton
If the presence of emotions in fingerprint exams would influence analysis

13 semi structured interviews

“How did you feel about succeeding in matching the prints”

Job satisfaction, catching criminals, long cases, need for closure

Question 6

Motivating Factors: Influence of Crime Type on Emotions

Answer 6

Situational

Dror et al (2005)

Manipulation of IV (low or high emotion)

27 Uni students

96 Fps (Half were clear, half were ambiguous)

Where a match between FPs was ambiguous, PPs were influenced by contextual info

Question 7

Motivating Factors: Need for Cognitive Closure

Answer 7

Individual & Situational

Completion of their part
Kruglanski (2006) found that when the need for cognitive closure is higher judgements are made quicker and with more confidence.

Question 9

Cognitive Bias: Observer/Expectancy Bias

Answer 9

When the expert anticipates the outcome because of the information from an initial observer

Question 10

Cognitive Bias: Selective Attention

Answer 10

Prior Expectation can lead to the filtering out of ambiguous elements in a partial or ambiguous print

Question 11

Observer Bias/ Expectancy Bias in the Brandon Mayfield case

Answer 11

Observer = When the 4th Bureau also confirmed the print after the FBI did

Expectancy = Brandon’s conversion it islam & army links (Prejudice)

Question 12

Selective attention in the Brandon Mayfield case

Answer 12

Admission to overlooking easily observed dissimilarities between the 2 prints

Question 13

Conformity Effect

Answer 13

If asked to validate the decision of a peer this may unconsciously bias them to agree with the original decision

Question 14

Need-determination perception

Answer 14

Bias arising from a strong desire to solve a crime

Question 15

Need-determination perception in the Brandon Mayfield case

Answer 15

It was a terrorist attack - 191 dead

Question 16

Overconfidence bias

Answer 16

Experts think they are always right even when faced with contradictory evidence.

Question 17

Overconfidence bias in the Brandon Mayfield Case

Answer 17

A match wad declared even though there were points if dissimilarity FBI blamed low resolution photos

Question 18

Background to Hall & Player

Answer 18

FPs are often incomplete, smudged, distorted or rotated, so identification is conducted by 2 experts to increase the reliability of the conclusion

FP experts can make mistakes which is why decisions must be verified before reported

The metropolitan police provide the experts with a copy of the crime scene report - which introduces an emotional bias

Question 19

Hall & Player: Method

Answer 19

Field Exp
IMD - random allocation between groups

IV: Low emotional or high emotional context
DVs:
1. Whether the PPs thought it was a match, not a match, insufficient, insufficient to identify
2. Whether they had read the crime scene report
3. Whether they thought the information in the report affected their analysis

Question 19

Hall & Player: Aims

Answer 19

Does the written report of a crime affect a FP expert’s interpretation of a poor quality mark?

Are the FP experts emotionally affected by the circumstances of the case

Question 20

Hall & Player: Sample

Answer 20

Self selected sample of 70 FP experts from the metropolitan police

Mean length of experience was 11 years