Criminal=> The collection + processing of forensic evidence

Question 1

Key research=> Hall + Player

Will the introduction of an emotional context affect fingerprint analysis design-making for experts?

Answer 1

-70 fingerprint experts from metropolitan police=> mean experience= 11 years
-See if set of fingerprints matched the ones on the £50 notes
Independent groups design=>
*Low emotional context condition= victimless crime with minor sentence= tried to pay for goods with forged £50 note
*High emotional group= note belonged to someone suspected of firing 2 gunshots
-Had to decide if fingerprints matched, didn’t match, wasn’t enough detail to analyse or so agreement but not enough to match
-Completed questionnaire of how they came to decision + if they had crime report- whether that affected their decision

• 50% of high emotional context= said it influenced their decision
• 6% of low emotion content
• No significant difference between high + low emotion groups
• Emotional context doesn’t reduce a fingerprint experts ability to make a final decision
• Many experts choose not to read crime report=> capable of analysing fingerprints in an objective way

Question 2

Dror=> top-down biases

Answer 2

Bottom up= examination of ridges + patterns of fingerprints to identify unique features

Top down= experts use previous experience + knowledge to make assumptions + identify fingerprints (used if they are degraded) Can lead to more errors=

• Expectancy bias= experts anticipate outcome- preconceived expectations
• Selective attention= prior expectation can lead to filleting out of ambitious elements
• Conformity effect= expert asked to validate decisions of a peer- unconsciously bias to agree
• Need-determination perception= strong desire to solve a crime

Question 3

Dror=> research with 27 students

Answer 3

• 27 uni students- (non experts)=> match 96 pairs of fingerprints
• 1/2 were clear + 1/2 were ambitious (top-down)
• Low emotion crime= burglary
• High emotion crime= murder
• Some of high emotion cases= subliminal messages (guilty) flashed up on screen
• Participants were more likely to find matches between fingerprints if they were high emotion
• Subliminal messages increased matches

Question 4

Miller=> six pack idea

Answer 4

Hair sample analysis

• Hair experts are susceptible to need determination bias
• Instead of giving experts 1 hair=> given 1 hair from crime scene + 4 fake hairs + 1 from suspect
• Experts know most are not from suspect=> makes them more hesitant
• Group using 6 pack method made less false positives- compared to group using 1V1 method

Question 5

The ACE-V method compared to Kassin linear approach

Answer 5

• Analysis= see if it’s suitable for comparison
• Comparison= analyse characteristic attributes of fingerprints
• Evaluation= exam answers questions
• Verification= verified by peer review

Kassin et al- linear approach
Normally finger analysts look at fingerprints from crime scene to compare to suspects print= circular approach (bias)
-Analyse crime scene print on its own=> look for unique features
-Analyse suspects print on its own + look for unique features
-Then compare notes + see if they match
More objective