Dr. Michelle Cowley Centre for Socio-Legal Studies May 19th 2010  How do people represent evidence in mind?  Why is mental representation important for psychology?  Why is mental representation important for evidence law?  Lens 1: The self representation  Lens 2: The expert representation  Lens 3: The anchor representation...  Conclusions  Future directions Mental Models  Principle of Truth  Principle of Parsimony  Principle of Consistency  Alternative Possibilities  Qualitative Weighting Weighting Models Theories  Principle of Independent Weighting  Principle of Inclusiveness  Principle of Quantification Johnson-Laird (2006), How people reason (e.g., Oaksford & Chater, 2007)  From logical tasks to legal contexts: Confirmation bias  In the 2-4-6 task participants are asked to discover a rule that the number sequence 2-4-6 conforms to:  And they tend to generate the hypothesis 'even and ascending in twos'.  And they tend to generate positive tests such as: 10-12-14, 16-18-20, 22-24-26...  The experimenter responds 'yes' because these tests fit with the true rule, which is in fact 'any ascending number sequence'.  These positive tests correspond simultaneously with the hypothesis and the truth.  Unless a negative test (i.e., refutation) of the hypothesis (1-5-9), which is consistent with the truth but inconsistent with the hypothesis is prompted, then participants will never discover the truth. Figure 1: Embedded false hypotheses in the 2-4-6 task and prejudiced thinking (Wason, 1960). U Even, 2, Asc True rule U Jewish stereotype Einstein/ Anne Frank Embedded false hypothesis in the 2-4-6 Task: Embedded false hypothesis in stereotypical thinking: Participants:  Thirty-Two participants  There were 23 women and 9 men (age range: 20 to 75 years; mean = 51 years).  No participants had taken courses in the philosophy of science. Design & Procedure:  2x1 (Your hypothesis is 'even numbers ascending in twos'; Peter's hypothesis is 'even numbers ascending in twos')  Recording booklet (triples, positive and negative tests and expectancies)  20 minutes on average Cowley & Byrne (2005), Cowley (2017) P < .01 P < .01 a b c d e f g h 8 7 6 5 4 2 1 3 Figure 4: A representation of a chess board middle game, in which it is white to play. Ps. Ten novices and ten Masters Design: 2x2 (expert lev * normal/random position) Materials: Dynamic equilibrium (n = 6) Procedure: Think aloud (3 min per position), recorded Protocol Analysis: Segmentation Cowley & Byrne (2005), Cowley (2017) Fig 5: A subsection of a grandmaster's evidence search tree Bc3 Retrospective EvaluationStarting Position Node Terminal Node Possible Refuting Evidence Qg2 Rxa3 bxa3 f5 gxf5 + - -Nxc3 Cowley & Byrne (2005), Cowley (2017) Table 1: The nine possible hypothesis types based on the subjective and objective evaluations of move sequences Retrospective evaluation Objective evaluation by Fritz by chess player Positive (+) Negative (-) Neutral (=) _____________________________________________________________________ Positive (+) +/+ +/- +/= Negative (-) -/+ -/- -/= Neutral (=) =/+ =/- =/= ______________________________________________________________________ Key: '+' refers to a positive evaluation, '-' to a negative one, '+/-' means the player's evaluation was positive and the program's evaluation was negative. Normal positions Randomised positionsP < .01 Table 2: The criteria relevant to the disclosure of prior convictions under trial conditions (CJA, 2003; Section 100(3)). ________________________________________________________ (3) In assessing the probative value of evidence for the purposes of subsection (1)(b) the court must have regard to the following factors (and to any others it considers relevant)- (c) where- (ii) it is suggested that the evidence has probative value by reason of similarity between that misconduct and other alleged misconduct. ________________________________________________________ Inconsistent findings over 40 years Evaluating appropriate use re CJA (2003 is problematic, Evidence based evaluation should be extensive, Theoretical framework to explain inconsistencies... 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 auto-theft 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. 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...  Figure 8: Mean underlying rating of guilt when one, two, and no prior conviction evidence was disclosed. Cowley & Colyer (Psychology, Crime, & Law 2010) • Seventy-two participants, 24 men and 48 women. Age range 1853years, 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 lefthanded person. David Baxter is left-handed or • Forensic evidence showed that the blow was delivered by a righthanded person. David Baxter is right-handed Figure 9: The number of jurors from a jury (n = 12) who chose 'guilty', 'not guilty', or 'cannot decide'. Cowley & Colyer (Psychology, Crime, & Law 2010) Figure 10: The pattern of positive evidence statements generated in the absence and presence of a similar prior conviction. Cowley & Colyer (Psychology, Crime, & Law 2010) Figure 11: The pattern of alternative possibilities indicative of innocence generated in the absence and presence of a similar prior conviction. Cowley & Colyer (Psychology, Crime, & Law 2010)  In Experiments 1 and 2, they were presented with vignettes describing the actions of two agents and a subsequent outcome affecting a third party in six vignettes, e.g.: In a tower block Mr. Jones, a contractor, left open an unguarded lift shaft. Mr. Peters knew that this was the case and invited Thomas to step inside. Thomas was badly injured. Or In a tower block Mr Peters invited Thomas to step inside an open lift shaft when he knew that the life wasn't there. He was badly injured. In a tower block Mr. Peters left open an unguarded life shaft, and David stepped inside the shaft but the lift wasn't there. He was badly injured.  The enabling condition is the unguarded lift (elevator) shaft, which enables Peters' invitation to cause Thomas' injury.  On our account, individuals tend to focus on the salient case in which enabler, cause, and outcome co-occur (Frosch, Cowley, & Johnson-Laird, under review). Figure 12: Mean ratings on the four 5-point scales for causes and enablers in Experiment 1. Bars are standard error Frosch, Cowley, & Johnson-Laird (under review) 0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 5 Cause/enabler Responsible Prison Damages M e a n r a ti n g o n f iv e p o in t s c a le cause enabler  Figure 13: Mean ratings on the four 5-point scales for causes and enablers in Experiment 3. Bars are standard error. 0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 5 Cause/enabler Responsible Prison Damages M e a n r a ti n g o n f iv e p o in t s c a le cause enabler Frosch, Cowley, & Johnson-Laird (under review)  Mental representations guide evidential reasoning, conclusiveness vs evidence value (e.g., Johnson-Laird, 2006; Cowley & Byrne, forthcoming)...  The impossibility of assigning precise probative value...  Independence evidence assumptions do not always hold...  Advocate lenses (self and expert) affect evidence interpretation...  Anchor lenses can suppress alternative possibility generation...  DNA evidence and mental representation vs quantifiable probative value (experiments in progress)...  Intentionality and representation in causal reasoning (ESRC proposal in submission), and the cognitive processes involved in victim blaming.  Layered sequences of experiments to build additional complexity into the experimental framework...  Group deliberation versus individual deliberation...  Developing the theory of mental models for legal reasoning... Funding thanks to: The Irish Research Council for the Humanities and Social Sciences, The Trinity Trust, Trinity College Dublin, The University of Southampton Grant for New Researchers, and the Socio-Legal Studies Association for funding. Research assistance thanks to: Laura Pennicott, Juliette Colyer, Avanti Perera and Paul Honey for research assistance.  Bornstein, B. H. (1999). The ecological validity of jury simulations: Is the jury still out? Law & Human Behaviour, vol. 23(1), pp.75-91.  Bright, D. A., & Goodman-Delahunty, J. (2006). Gruesome evidence and emotion: Anger, blame, and jury decision-making. Law & Human Behaviour, vol. 30(2) , pp.183-202.  Bull-Kovera, M. B. (Ed.) (2017). The Psychology of Juries. Washington, USA: American Psychological Association (APA). USA.  Cowley, M. (2017). Hypothesis Testing: How We Foresee Falsification in Competitive Games. Saarbrucken, Germany: Lambert Academic Publishing  Cowley, M. (2017). 'The Innocent v The Fickle Few': How Jurors Understand Random-Match-Probabilities and Judges' Directions when Reasoning about DNA and Refuting Evidence. Journal of Forensic Science & Criminal Investigation, 5(3): 2017  Cowley, M. (2014). M-Level Quantitative Methods in Socio-Legal Studies: A Methodology Clinic Workbook – CSLS, University of Oxford. Law Educator: Courses, Materials, & Teaching SSRN eJournal Catalogue.  Devine, D.J. (2012). Jury decision making: The state of the science. New York: New York University Press.  Cowley-Cunningham, M. (2018). Children & the Law: Courtroom Research Basics for Busy Practitioners (Booklet – Presentation Slides). Law & Society: Courts eJournal, vol. 12, Issue 36: 25 May, 2018. Law & Society SSRN eJournal Series sponsored by the Maurer School of Law, Indiana University.  Cowley-Cunningham, M. (2019). Psychology of Law: 3 Critical Empirical Legal Problems. Law & Society: Criminal Procedure eJournal, vol. 14, Issue 24: 24 April, 2019. Law & Society SSRN eJournal Series sponsored by the Maurer School of Law, Indiana University.  Cowley-Cunningham, M. (2020). For the Sake of Justice: Societal Expectations of Foreseeability Weigh Heavily for Jurors Judging in Child Death Cases. Forthcoming.  Cowley-Cunningham, M., & Colyer, J. B. (2019). Asymmetries in Prior Conviction Bias. Law & Society: Criminal Procedure eJournal, vol. 14, Issue 25: 01 May, 2019. Law & Society SSRN eJournal Series sponsored by the Maurer School of Law, Indiana University.  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.  Johnson-Laird, P. N. (2006). How We Reason. Oxford, UK: Oxford University Press.  Devine, D. J. (2012). Jury Decision Making: The State of the Science. New York, USA: New York University Press.  Devine, D. J. (2012). Jury Decision Making: The State of the Science. New York, USA: New York University Press.