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Defeating Conclusions from Legal Conditionals Should the person be punished? Defeating conclusions from legal conditionals Inaugural-Dissertation zur Erlangung des akademischen Grades Doctor rerum naturalium (Dr. rer. nat.) an der Justus-Liebig-Universität Gießen Fachbereich 06: Psychologie und Sportwissenschaften Otto-Behaghel-Strasse 10F 35394 Gießen vorgelegt von Dipl.-Psych. Lupita Estefania Gazzo Castañeda geboren am 08.03.1986 in Lima, Perú März, 2016 Supervisor and First Reviewer: Prof. Dr. Markus Knauff Second Reviewer: PD Dr. Dr. Marco Ragni DEFEATING CONCLUSIONS FROM LEGAL CONDITIONALS Declarations Parts of this thesis have been published previously in different peer-reviewed journals and presented at peer-reviewed conferences. To facilitate readability I decided to embed and adapt these publications as chapters of a monograph, instead of a cumulative thesis. In the following I declare which material has been published previously and where: Chapter 3 has been published in a slightly different form in: Gazzo Castañeda, L. E., & Knauff, M. (2016). Defeasible reasoning with legal conditionals. Memory & Cognition, 44, 499-517. doi: 10.3758/s13421-015-0574-7 (with permission of Springer) Chapter 5 has been published in a slightly different form in: Experiment 6-7: Gazzo Castañeda, L. E., & Knauff, M. (2016). When will is not the same as should: The role of modals in reasoning with legal conditionals. The Quarterly Journal of Experimental Psychology, 69, 1480-1497. doi: 10.1080/17470218.2015.1085067 Experiment 8: Gazzo Castañeda, L. E., & Knauff, M. (2015). Defeasible reasoning with quantifiers. In D. C. Noelle, R. Dale, A. S. Warlaumont, J. Yoshimi, T. Matlock, C. D. Jennings, & P. P. Maglio (Eds.), Proceedings of the 37th Annual Conference of the Cognitive Science Society (pp. 770-775). Austin, TX: Cognitive Science Society. Chapter 6 has been published in a slightly different form in: Experiment 9: Gazzo Castañeda, L. E., Richter, B., & Knauff, M. (2016). Negativity bias in defeasible reasoning. Thinking & Reasoning, 22, 209-220. doi: 10.1080/13546783.2015.1117988 As a consequence of my embedding these publications in a monograph, there is also some overlap of this thesis’ Aims and Hypothesis (Chapter 2) and General Discussion (Chapter 7) and the introductions and discussions of the respective publications. i DEFEATING CONCLUSIONS FROM LEGAL CONDITIONALS Acknowledgments First, I want to thank my supervisor Prof. Dr. Markus Knauff for giving me the possibility to investigate such an interesting topic were I could combine my two favorite psychological topics: cognition and legal psychology. Thank you also for your support and all the interesting and productive discussions. I want also to thank Dr. jur. Carsten Bäcker and Emma Harms for their advice on legal subjects. Next, I want to thank all my student assistants Lena Dienelt, Jessica Ewerhardy and Mohammad Nasiri for helping me collecting data, German proofreading, and interesting ideas. Further I want to thank all my colleagues for being there whenever I had questions or when I needed a break by going to the Mensa. And finally I also want to thank my friends, my family, and Victor for all the psychological support, love and the necessary times of distraction. This research was supported by DFG grant KN 465/10-1 and KN 465/10-2 to Markus Knauff within the DFG Priority Program “New Frameworks of Rationality”. ii DEFEATING CONCLUSIONS FROM LEGAL CONDITIONALS Zusammenfassung Anfechtbares Denken (defeasible reasoning) beschreibt die Fähigkeit von Menschen, zuvor gezogene Schlüsse im Lichte neuer Information zu revidieren. Es ist besonders in der Rechtsprechung wichtig, weil dort strafausschließende Umstände dazu führen können, dass Richter schlussfolgern, dass eine strafbare Handlung nicht bestraft werden soll. Das Ziel dieser Arbeit ist es daher zu untersuchen, wie Menschen Schlussfolgerungen von rechtlichen Regeln revidieren. In einer Reihe von Experimenten wurden rechtliche Regeln als Konditionale präsentiert (z.B. „Wenn eine Person einen Menschen tötet, dann soll die Person wegen Totschlags bestraft werden“) und in Inferenzaufgaben zusammen mit potenziell strafausschließenden Umständen (z.B. Notwehr) eingebettet. Strafausschließende Umstände wurden entweder explizit als eine dritte Prämisse präsentiert (Experimente 1, 2, 4, 5) oder durch Vorstudien implizit erfasst (Experimente 6-8). Die Versuchsteilnehmer sollten entscheiden, ob der in der Inferenzaufgabe beschriebene Täter bestraft werden soll (Experimente 1, 2, 4-8) oder bestraft wird (Experimente 6-7). In Experiment 3 wurden die Versuchsteilnehmer aufgefordert strafausschließende Umstände selbst zu generieren. In allen Experimenten hatten die Versuchsteilnehmer kein rechtliches Vorwissen (d.h. Laien), aber in den Experimenten 1-3 wurden auch Juristen (d.h. fortgeschrittene Jura-Studierende oder Jura- Absolventen) getestet. Während Juristen beim Schließen den Regeln des Strafgesetzbuches folgten, hatte das Gerechtigkeitsempfinden von Laien einen Einfluss auf ihre Schlussfolgerungen. Wenn Laien gefragt wurden, ob ein Täter bestraft werden soll und die Straftat moralisch empörend war, ignorierten sie oft potentielle strafausschließende Umstände. In solchen Fällen hatten Laien sogar Schwierigkeiten selbst strafausschließende Umstände zu generieren. Nur wenn Laien danach gefragt wurden, ob ein Straftäter bestraft wird, konnten sie Ausnahmen für moralisch besonders verwerfliche Straftaten berücksichtigen. Des Weiteren konnte gezeigt werden, dass abhängig von den Einstellungen und Präferenzen der Teilnehmer manchmal rechtlich strafbare Taten nicht bestraft wurden. Zwei weitere Experimente (Experimente 9-10) zeigen, dass Menschen auch in Alltagssituationen oft Ausnahmen für emotional geladene Ereignisse ignorieren. Die Befunde sind für die kognitive Psychologie relevant, weil sie die Wichtigkeit von Vorwissen, Einstellungen und Präferenzen beim Denken zeigen. Außerdem sind sie für die Rechtswissenschaften, Sozialpsychologie und unserer Gesellschaft bedeutsam: die Ergebnisse zeigen, dass Paradigmen der kognitiven Psychologie verwendet werden können, um sozial relevante Konstrukte aus der Rechtstheorie und Sozialpsychologie zu testen. iii DEFEATING CONCLUSIONS FROM LEGAL CONDITIONALS Abstract Defeasible reasoning is people’s ability to withdraw previously drawn conclusions in light of new evidence. Defeasible reasoning is therefore especially important in law, where exculpatory evidence can bring judges to conclude that an offence should not be punished after all. The aim of this thesis was thus to investigate how people withdraw conclusions from legal rules. In a series of experiments, legal rules were presented as legal conditionals (e.g., “If a person kills another human, than the person should be punished for manslaughter”) and embedded in inference tasks together with potentially exculpatory circumstances (e.g., self- defense). Exculpatory circumstances were presented either explicitly as a third premise (Experiments 1, 2, 4, 5), or captured implicitly via preliminary studies (Experiments 6-8). Participants had to decide whether the offender described in the inference task should (Experiments 1, 2, 4-8) or will be punished (Experiments 6-7). In Experiment 3 participants were asked to generate exculpatory evidence. Participants in all experiments were people without legal education (i.e., laypeople), but in Experiments 1-3 lawyers (i.e., advanced law students and graduated lawyers) were also tested. Whereas lawyers’ defeasible reasoning adhered to the rules of penal code, the results showed that laypeople’s defeasible reasoning depended on their own sense of justice. When asked whether an offender should be punished, laypeople ignored potential exculpatory evidence when the offence was highly morally outraging. In these cases, laypeople even had difficulties in retrieving exculpatory evidence from memory. Only when laypeople were asked whether an offender will be punished, were they more willing to also consider exceptions for highly morally outraging offences. Moreover, depending on people’s attitudes about offences and offenders, sometimes legally punishable actions were not punished. Two additional experiments (Experiments 9-10) suggested that people are also prone to ignore exceptions for emotionally-charged events in everyday scenarios. The findings are relevant for cognitive psychology because they show the importance of considering domain knowledge and the reasoners personal attitudes and preferences when predicting inferences. Moreover, the results also have implications for law, social psychology, and society: they show how cognitive paradigms can be applied to test socially relevant constructs from legal theory and social psychology. iv DEFEATING CONCLUSIONS FROM LEGAL CONDITIONALS Table of Contents Introduction .............................................................................................................................. 1 Chapter 1: Theoretical Background ....................................................................................... 5 1.1. Conditional Reasoning ................................................................................................... 5 1.1.1. Defeasible Reasoning ......................................................................................... 11 1.1.1.1. The Content of Conditionals .................................................................... 12 1.1.1.2. The Context of Conditionals .................................................................... 18 1.1.2. Theories on Conditional
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