Asymmetries in Prior Conviction Bias (Presentation Slides, - PDF document

See discussions, stats, and author profiles for this publication at: https://www.researchgate.net/publication/332416846 Asymmetries in Prior Conviction Bias (Presentation Slides, Accompanying Notes to Cowley & Colyer, 2010) Article in SSRN Electronic Journal · January 2019 DOI: 10.2139/ssrn.3353138 CITATIONS READS 0 5 2 authors , including: Michelle B. Cowley-Cunningham Royal Statistical Society 107 PUBLICATIONS 141 CITATIONS SEE PROFILE Some of the authors of this publication are also working on these related projects: Research Methods View project Survey Marketing for Border and Ireland North-East: Quantitative and Qualitative Real-Time Regional Marketing View project All content following this page was uploaded by Michelle B. Cowley-Cunningham on 28 October 2019. The user has requested enhancement of the downloaded file.

Asymmetries in prior conviction bias Dr. Michelle Cowley Centre for Socio-Legal Studies University of Oxford Juliette B. Colyer School of Psychology University of Plymouth

Overview *New Summary Presentation Slides (2019) to: Cowley, M., & Colyer , J. B. (2010). Asymmetries in prior conviction reasoning: Truth suppression effects in child protection contexts, Psychology, Crime and Law , 16(3), 211-231.  Illustrative example: child abuse cases  The legal context  Psychological studies on prior conviction bias  A new theory of mental representation  Predictions and quantitative experiment design  Pilot study: Underlying ratings of guilt  Study 1: Prior convictions and forensic evidence  Study 2: Prior convictions and community disclosure

Megan’s Law • Megan Kanka was killed by a sex offender who unknown to her community lived in her neighbourhood. • Within months, New Jersey passed emergency legislation for a compulsory notification for sex offenders with previous convictions. All states in the US passed this legislation. • ‘Megan’s Law will protect tens of millions of families from the dread of what they do not know’ (Bill Clinton, 2000, cited in Pawson, 2006).

Criminal Justice Act (2003) • The Criminal Justice Act outlines law governing prior conviction disclosure (2003, Ch.1, part 11, sections 98-113). • Namely, that it is now admissible to disclose proof of a prior conviction. • the law of criminal evidence should generally move towards trusting judicial and lay fact finders when they assign weight to relevant evidence • and move away from a clinical use of technical rules of admissibility[1][2]. • The criteria of interest in child abuse cases is where: • (i) the evidence is evidence of a person’s misconduct, and • (ii) it is suggested that the evidence has probative value by reason of similarity between that misconduct and other alleged misconduct. [1] ‘Review of the Criminal Courts of England and Wales’ (HMSO, 2001) [2] The Law Commission report ‘Evidence of Bad Character in Criminal Proceedings’ (Law Commission, No 273, cm 5257, 2001)

Studies of prior conviction bias Prior convictions in real cases • Kalven & Zeisel (1966)- 27% more often • Bottoms & Goodman (1994)- child witness corroboration Limiting instructions and diffusion • Greene & Dodge (1995)- credibility vs guilty • Doob & Kirshenbaum (1973)- time for pc Deliberation and alternative stories • London & Nunez (2000) • Pennington & Hastie (1986) Similarity and dissimilarity of prior conviction • Wissler & Saks (1985)- murder and autotheft

A new theoretical element: Mental Representation • Inconsistent findings over 40 years • Evaluating appropriate use re CJA (2003) is problematic • Evidence based evaluation should be extensive • Theoretical framework to explain inconsistencies • Possibilities in mind (Johnson-Laird, 2006) • Principle of truth • Principle of consistency • Explicit alternatives and counterexample search

Predictions • We cannot assume consistent additive probative value for prior conviction evidence- prompting a primary mental representation of guilt. • Evidence that would be otherwise considered irrelevant, may be attributed more relevance if it is consistent with a representation prompted by a prior conviction- lense of diffusion • This representation may prompt auxiliary stereotypical criminal representations including re-offending • Explicit evidence of ‘no prior convictions’ will be more difficult to process than explicit evidence of a prior conviction. • Prior conviction evidence suppresses alternative possibilities

Pilot study  Fifty one participants: 8 men and 43 women  Mean age 20.64years, range from 19 to 33 years  Design: 1 x 3 (control, one previous, two previous)  Materials: Reasoning about a scenario created from a real life case of a child who was killed by a man with two previous convictions for similar offences.  On January 2, 2006, David Baxter had been arrested. He had been accused of killing 18-month- old Joanna Connolly. Joanna’s skull had been fractured when she received a physical blow to the head. She was the daughter of Susan Connolly, the woman who David Baxter had been seeing.

Pilot study Knowledge of previous convictions (one; two; none): David Baxter had previously served a three year sentence for being physically abusive towards an ex- girlfriend’s three year old girl in 2003. Please answer the following questions: Q.1 Please tick whether you think: David Baxter is guilty __ David Baxter is not guilty __ You cannot decide __ Q.2 On a scale of 1 to 10, circle the number that you think best reflects how guilty you think David Baxter is…

Pilot study Fig 1. Percentage of verdict type per condition. Regardless of the number of previous convictions people could not decide if the defendant was guilty. Chi 2 = 75.444 (2), p <.0005

Pilot study Fig 2. Underlying ratings of guilt were higher when a previous conviction was present than when a previous conviction was not present regardless of the number of previous convictions. Kruskal-Wallis chi 2 = 16.162 (2), p <.0005

Experiment 1  Seventy-two participants , 24 men and 48 women. Age range 18- 53years, mean 22.4years  Design 3 x 2 between subjects (left-handedness, right-handedness, no handedness) x (previous conviction, no previous conviction) [6 conditions]  Materials: The same scenario and measures either with or without a previous conviction and sort of handedness:  Forensic evidence showed that the blow was delivered by a left-handed person. David Baxter is left-handed or  Forensic evidence showed that the blow was delivered by a right-handed person. David Baxter is right-handed

Experiment 1 Fig 3. The number of people of a twelve person jury, who came to a ‘guilty’ ‘not guilty’ or ‘cannot decide’ verdict in the presence of evidence of handedness (RH or LH) and/or previous convictions (PC). …People tend to significantly choose ‘cannot decide’ more often except when a previous conviction is accompanied by evidence of a left handedness match (PC and LH).

Experiment 1 Fig 4. Underlying mean ratings of guilt on a scale of 0-10 were higher when a previous conviction was present than when a previous conviction was not present regardless of the number of previous convictions (Kruskal Wallis, chi2= 12.282 (5), p <.031).

Experiment 2 • Ps. 48 (15 men and 33 women). The mean age was 34yrs (range: 19- 86 yrs). Members of the public. • Design. 1 x 3 (3 envelopes randomly assigned: ‘…will be released’/ ‘…one similar pc and will be released’/ ‘…no similar pc and will be released’) • Materials. A man who is a convicted paedophile has made positive progress in prison. He has completed a strict, structured rehabilitation program which focuses on the prevention of re-offending. Q1. Do you think this man will re-offend? Q.3. Do you think it is important to be informed if this man was to be located in your community? Measures: Yes/ no/ cannot decide, Rate how strongly (scale 0- 10) ……………………………………………………………………………………..

Experiment 2: PC vs No PC One similar PC: • Before: Yes (19%), No (6%), Re-offend Cannot decide (75%, p <.005) • After: Yes (81%), No (6%), Cannot decide (13%, p <. 005) • Before (M = 5.19) vs After (M = 6.81, p <.05) No similar PC • Before: Yes (44%), No (6%), Cannot decide (50%), p >. 05) • After: Yes (38%), No (6%), Cannot decide (56%), p <.05). • Scale: M = 6.19 vs M =6.00 ns .

Experiment 2 continued… One similar PC Before: Yes (56%), No (19%), Cannot Reveal Identity decide (25%) p <.05 100 80 62 56 After: Yes (62%), No (19%), Cannot 60 decide (19%) p <.05. 25 40 19 19 19 20 0 Scale: Before (M = 6.63) vs After (M = 6.63). ns Yes No Cannot decide Before envelope After envelope Reveal Identity No similar PC Before: Yes (31%), No (31%), Cannot decide (38%), ns After: Yes (38%), No (31%), Cannot decide (31%), ns Scale: Before M = 4.56 vs After M = 5.56, ns

Experiment 2 continued… Pose danger 100 One similar PC 81 80 Before: Yes (38%), No (0%), Cannot 62 decide (62%), p <. 05. 60 38 40 19 After: Yes (81%), No (0%), Cannot 20 0 0 decide (19%), p <.005. 0 Yes No Cannot decide Scale: Before (M = 5.25) vs After (M = 7.31), p <.005. Before envelope After envelope Pose danger No similar PC Before: Yes (56%), No (6%), Cannot decide (38%), p <. 05. After: Yes (44%), No (6%), Cannot decide (38%), p >.05. Scale: Before (M = 6.63) vs After (M = 6.00), p >.05.