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Sue Hunter - Open University
Grant Walker & Melanie Lamb - Stirling University
What jurors do with evidence during jury deliberation? Sue Hunter Open University Grant Walker Melanie Lamb
Right to trial by impartial jury, protected by law from influence BUT jury deliberation is difficult! have to disagree with each other! Schudson (1997)
What do we know? Best predictor of final jury verdict = Distribution of pre-deliberation juror verdicts Ellesworth (1989) Majority influence
What do we know? Judge & Jury agreement on who should be found guilty chance levels! Kalven & Zeisel (1966) 9% cases hung 74% cases Judge and juries agree 17% cases : 57% judge ►likely convict / jury ►likely acquit so agreement for these 1083 cases at chance levels Criticism : judge - hindsight bias Cameron and Tinsley (2001) Interviewed judge before jury verdict for 48 jury trials agreement 50% - no better than chance.
Explanations for lack of agreement judge & jury 1. Genuine leniency bias nullification by a jury - societal correction irrespective of what law says? 2. CSI effect Unrealistic reliance on the infallibility of scientific evidence ? (Lord Justice Leveson, 2009, “forensics = silver bullet”) 3. Lay perceptions of the law rather than legal definitions of the law? e.g. jurors must be 100% certain of guilt – unrealistic high standard (Ogloff & Rose, 2005) 4. Or is it because the jurors do not understand the evidence?
Theoretical models Group Decision making - Process
Demonstrability affects outcomes Eureka problem truth wins (1) Lower demonstrability truth supported by one (2) Low demonstrability majority, equi-probability otherwise (3:1 OR 2:2) Complexity judgement comes into play (15!)
Levine (1999) Abstract fact-finding Consensus continuum Demonstrability affects outcomes Focus Problem solving No correct answer, achieve consensus Task intellective judgemental Emphasis correct solution thro’ information processing selection of alternatives
Theoretical models Minority Influence Moscovici (2000) Majority focus on minority = response bias (consensus reasoning) majority influence as an acceptance Minority focus on information (problem solving) minority influence persistent consistency RESPONSE CONFLICT
Theoretical models Moderate motivation High Motivation Minority Central processing of information Majority Heuristic processing of information Focus on others Minority Central processing of information Majority Central processing of information Persuasion & Minority/majority influence Martin & Hewstone (2008) Majority heuristic cues /minority elaborative central processing
Research Question Does deliberation behaviour change in the presence of an evidence-based minority? Does deliberation behaviour change if the number of evidence based jurors increases?
Approach Process Cognitive Ethology: Kingstone, Smilek & Eastwood (2008). Stability tied to situation emerges when several variables allowed to vary simultaneously. Natural variance measured to reveal key characteristics that emerge when variables are “free to co-occur”.
Procedure Relevant Script read judge’s instruction and court transcript individually Convened as a jury (15) Deliberation recorded on an audio digital recorder - transcribed Peripheral evidence (CCTV) at end (unanimous not-guilty ►evidence based minority of 2) Peripheral evidence (CCTV) at start More evidence based guilty verdicts + confederates (unanimous not-guilty ►plurality ►guilty majority)
Analysis Number of evidence-based jurors (guilty verdict) Topics discussed & percentage contribution by each juror Identification of semantic barriers Proximity Coefficient analysis
14 11 Juries: peripheral evidence (CCTV) end verdict number Straw poll Unanimous 6 5 Silent minority (1) 4 4 Active minority (1) 2 1 Active minority (2) 2 1
What difference did the presence of a minority make? Time on topic Time key witness alterations Unanimous 62% 55% 1 Unanimous 91% 44% 2 Unanimous 83% 11% 10 Unanimous 82% 15% 11 Unanimous 81% 2% 11 Unanimous 83% 24% 17 Silent EB minority (1) 19% 1% 3 Silent EB minority (1) 59% 64% 5 Silent EB minority (1) 38% 41% 12 Silent EB minority (1) 57% 44% 24 Active EB minority (1) 63% 44% 16 Active EB minority (1) 92% 57% 32 Active EB minority (2) 64% 64% 24 Active EB minority (2) 62% 76% 46
Semantic Barrier Analysis Semantic barriers: positioning Moscovici (2000), Gillespie (2008). Representation of the ‘alternative’ within the core To maintain the core representation semantic barriers are used to distance the ‘alternative’ – protects core Identification of semantic barriers e.g. alteration of evidence: “ It is the twelve inch blade, if it was a wee tiny glint how are you going to miss this big whopper of a blade ” Original : ‘7 inch blade’ & ‘glint of metal’
semantic barriers identified Coroner ≠ key witness description 6 Driver did it 11 Wild theory generation 13 Ridicule of the minority –emotional pressure 18 Reasonable doubt – redefined 27 Absence of evidence (CSI) 35 Only one witness 36 Discrepancy clothing descriptions (confirmation bias) 57 Insufficient evidence 58 Alteration/denial of evidence to negate key witness 65 Negation of key witness disposition (young, adrenaline) 72
Coroner ≠ key witness description (6) 156 Em, the, the witness who saw him being stabbed said that his hand was in the air and it came down upon his chest but the wound was a vertical wound through his rib so that didn’t fit Explanation based reasoning! Coroner (vertical) consistent with key witness (down) – correctly cited but meaning change to be inconsistent.
Wild Theory (13) 156 But his hand could have been up in the air calling for help and he could have put his hand on to try and stop the bleeding or something and the victim has fallen, he’s maybe got scared and ran away Explanation based reasoning! An alternative story generated to explain evidence
Reasonable Doubt (27) 73 I mean a lot of the points are valid, but there’s a doubt in my but there’s a doubt in my mind that she 100% saw exactly what happened so you can’t find him guilty 98 I don’t know I wasn’t like a 100% sure Unrealistic expectation: reasonable doubt redefined as 100% sure Points made by an evidence-based juror are accepted as valid, but despite evidence pointing to guilt the non-evidence based juror does not accept the alternative representation. Reasonable doubt (redefined as 100% sure) is ‘used’ as a semantic barrier to distance the alternative & protect the core representation of not-guilty.
Absence of evidence - CSI effect (35) 31 .. for guilty you need to have like the murder weapon and some kind of actual solid evidence rather than just a witness statement 73 ... maybe if they found the weapon he’s be guilty you know if they got DNA from it 48 He’s not on camera footage either Absence of ‘concrete’ evidence is used as a semantic barrier to maintain not-guilty position. Negative reasoning was common.
Negation of Key Witness (72) 64 so she can’t have witnessed it properly whilst mucking about with her clips Note original : “ As I stood up I saw a man jump from the side door of the van” The original evidence has been elaborated on so that it discredits the key witness.
Recategorisation of meaning: reasonable doubt redefined
guilty = “must be definite he did it”
“ don’t know” = not guilty
Guilt Not-Guilty Correct evidence .97 .98 .98 .95 .92 .99 Incorrect evidence Alteration of evidence to negate key witness testimony Majority pressure Response to verdict choice Only minority guilty verdicts associated with correct citation of evidence
Response to incorrect evidence Alteration of evidence negates key witness .96 Alternative story generation Confirmation bias .95 .95 MAJORITY MINORITY correct evidence 100 Incorrect evidence story correction evidence correction .95 .95
Response to ridicule Alteration of evidence negates key witness .99 Negation key witness’s disposition confirmation bias to negate key witness .99 .98 MAJORITY MINORITY Restate correct evidence .99 personal ridicule of minority Only one witness .95 Correct inferences .97
Reasonable doubt Responses to reasonable doubt Minority remain with the evidence but the majority do not correct evidence MINORITY MAJORITY .97 Guilt .95 Evidence-based inferences .96 absence of a weapon .97 alteration of evidence negates key witness .96 denial of evidence .96 alternative story generation .95 negation of key witness’s disposition .93
minority did process evidence, the majority did not
majority did not process the majority argument in detail either - consistent with majority influence as an acceptance.
Incorporating the alternative into the core presentation required
more elaborate narratives to keep in line with the pre-determined position (tied themselves in knots)
When no straw poll, facilitation (open questions & summaries) instigated problem solving of evidence, BUT once positions emerged, the majority changed focus onto the minority - pressure for consensus
What do juries do with evidence during deliberation?”
Juries: peripheral evidence (CCTV) start Jury no Number of members confederates Jurors GUILTY Evidence based Verdict change Start split (G;NG) Include any confederates Final jury verdict split G/NG Jury verdict Majority Not-guilty juries 1 15 0 1 5 change to NG 6:9 1:14 not guilty 12 15 0 2 1 changes to NG 3:12 2:13 not guilty 4 15 2 3 3 changed to NG before poll 2:13 2:13 not guilty Plurality juries – near equal split 5 15 2 3 2 changed to G before poll 7: 8 7:8 not guilty 6 15 3 2 3 changed to G before poll 8:7 8:7 guilty 3 14 1 6 1 changed to G before poll 8:6 8:6 guilty Majority Guilty juries 9 13 5 4 0 9:4 9:4 guilty 10 14 6 4 0 10:4 10:4 guilty 11 12 7 1 1 changed to guilty 8:4 9:3 guilty
Juror free recall: number of items (total = 30) / juror verdict Jury 4 – Majority not guilty Jury 5- Plurality Jury 9- Majority guilty Non-evidence based verdicts Not guilty Not guilty confusion Guilty Evidence based verdicts Guilty Not guilty No relation between juror verdict & number of items recorded Jurors introduced items in the jury that were not in their free recall Cannot use items recorded in free recall as measure of evidence recall
no difference in number of items mentioned in deliberation
When jurors understood the evidence corrections were made
When jurors did not understand the evidence, semantic barriers used to negate a guilty verdict
Correct evidence was cited
guilty- verdict was negated with semantic barriers
Evidence comprehension interacted with how jurors ‘used’ evidence
Evidence comprehension / evidence usage
Interaction: between presence of fabricator & verdict split both juries 4 & 3 contained fabricators Fabricator influenced when not challenged (jury 4) Fabricator did not influence when challenged (jury 3) Both change to NG / fabricator attack No change when support Juror number & percentage contributed to the discussion Jury 4. 42 45 46 47 48 49 50 51 52 53 56 EB G 57 EB G 58 4% 12% 9% 17% 25% 6% 1% 3% 7% 6% 1% Jury 3. 28 EBG 29 30 EB G 31 33 34 35 EB G 36 EB G 37 38 EB G 40 EB G 41 43 EB G 44 9% 19% 11% 11% 4% 22% 19% 9%
Both Jury 3 (19%) & jury 4 (25%) had a dominant contributor
who presented alternative interpretations of the evidence –
Fabricator supported - occupied 54% of deliberation time
against an evidence-based minority of 2 - occupied only 13%
Changed verdict to not-guilty.
Plurality jury with 7 evidence-based jurors of which 2 were
active (41%) against the fabricator (19%).
Fabricator challenged – no verdict change to not-guilty.
Fabricator/ juror participation/verdict split
Discrepancy between clothing Negation key witness’s ability CSI effect Absence of evidence Wild theory explanations Focus on reasonable doubt All juries Number of Semantic barriers in each jury Majority not-guilty Plurality not -guilty Plurality guilty Majority guilty Majority guilty (smaller juries) Semantic Barrier Analysis
Discrepancy between clothing Negation key witness’s ability CSI effect Wild theory explanations Focus on reasonable doubt high in 12 & 6 both contained fabricators high in 4 & 5 both plurality juries Not In Majority Guilty juries
Proximity Coefficient Analysis Statistical analysis allows identification of cued behavioural responses Also allows identification of ‘end-points’ in deliberation
Jury 12- Majority NG (13:2) 167 “ Nobody else agreed with her description” Incorrect evidence Questioning evidence Confirmation bias Negation of Key Witness Reasonable doubt Off-topic
“ so you couldn’t say for 100% certain that it was him”.
REASONABLE DOUBT Questioning evidence Confirmation bias Only one witness
Jury 10 Majority guilty 4NG:10G 132 “ I also can’t really see where the attacker comes from and that kinda bothers me as Gillian doesn’t say if he comes from the store, or if he’s on the pavement” Original: “ I saw a man jump from the side door of the van” CORRECT EVIDENCE Negation of Key witness
Conclusion Not-guilty verdict jurors: poor evidence comprehension No minority influence from evidence-based jurors As size of evidence-based minority increased the semantic barriers changed: Wild theory ►reasonable doubt ►negation key witness Deliberation was maintaining position
non-evidence based jurors then relied on strategies to
maintain their verdict driven position:
Reasonable doubt – only one witness
Negating the key witness’s ability = dispositional reasoning
Absence of evidence (CSI effect)
Conclusion When the not-guilty faction became the minority – “ you have made some good points, but…..” processed but did not accepted the guilty argument
Conclusion Relation to theoretical models: Decision-making process models – demonstrability Truth supported by one did not win Minority Influence/majority influence Persistent consistent minority did not influence Non-evidence based majority influence as acceptance Non-evidence based majority focus on minority (stigma) Persuasion/minority-majority influence Non-evidence based majority did not centrally process evidence Social representations Semantic barriers used only by non-evidence based jurors Position maintenance
Despite judge’s instruction ......consider all evidence first
Juries started with a straw poll
Why is this a problem?
Frames deliberation in terms of position
Only 8 out of 113 jurors (7%) changed verdict
but only 1 changed to evidence-based guilty (.08%)
Jurors DO NOT change position - Majority position ALWAYS wins!
Why is this a problem?
Majority still win when they have not understood the evidence!
If evidence-based jurors Understand the evidence Problem solve evidence Do not use explanation-based reasoning. Then…………….
What is the jury leniency bias? 1. Genuine leniency bias : nullification 2. CSI effect : reliance on the infallibility of scientific evidence 3. Lay perceptions of the law : not the strict legal definitions 4. Or is it because the jurors do not understand the evidence?
Then jury leniency bias is The leniency bias can occur because juries do not understand the evidence Evidence based jurors did not show a CSI effect Evidence based jurors did not redefine reasonable doubt The CSI effect & redefinition of legal terms were both a result of not understanding evidence
34/48 no systematic structure to assess evidence & apply law -foreperson crucial role here
Different levels of juror participation
20/48 dominant jurors significantly affected deliberation process & affected jury verdict – pressure to decide & in 6 cases jurors reported feeling intimidated (others implied it). Did not have the skills to control a determined vocal juror.
4/48 refusal to discuss rationally, adverse comments about opinion of others, personal insults, monopolising the process .
Led to others feeling uncomfortable about expressing their views , pressurised to reach a decision consistent with the dominant jurors who were usually in the majority
22/48 pressure came from other jurors. Confidence came with confirmation of their view from other jurors. Pressure to reach unanimous decision- minority compromise their principles. Common approach focus on minority.
35/48 fundamental misunderstandings of the law emerged. – read into the judge’s remarks interpretations not intended by the judge – to lever dissenting jurors.