3: How Judges Decide I: Theories and Preferences

Court rulings have an impact on individuals, economies and political systems. In principle, judgments follow from legal rules. But how do judges make decisions in practice? This week we review the most influential theories of judicial behaviour, the conditions under which they apply and the evidence produced in their support. We also look at how judges’ preferences are measured and how they manifest in decisions across a variety of political and judicial contexts.

Mandatory readings

Harris, Allison P., and Maya Sen. “Bias and judging.” Annual Review of Political Science 22, no. 1 (2019): 241-259. https://doi.org/10.1146/annurev-polisci-051617-090650

Riaz, Sascha, and Maik Hamjediers. “Anti-Immigrant Bias in the Choice Between Punitive and Rehabilitative Justice.” British Journal of Political Science 55 (2025): e147. https://doi.org/10.1017/S0007123425100884

Spamann, Holger, Lars Klöhn, Christophe Jamin, Vikramaditya Khanna, John Zhuang Liu, Pavan Mamidi, Alexander Morell, and Ivan Reidel. “Judges in the Lab: No Precedent Effects, No Common/Civil Law Differences.” Journal of Legal Analysis 13, no. 1 (2021): 110-126. https://doi.org/10.1093/jla/laaa008

Optional readings

Bonica, Adam, and Maya Sen. “Estimating judicial ideology.” Journal of Economic Perspectives 35, no. 1 (2021): 97-118. https://doi.org/10.1257/jep.35.1.97

Hanretty, Chris. “Dissent in Iberia: The ideal points of justices on the Spanish and Portuguese Constitutional Tribunals.” European Journal of Political Research 51, no. 5 (2012): 671-692. https://doi.org/10.1111/j.1475-6765.2012.02056.x

Posner, Richard A. “What do judges and justices maximize? (The same thing everybody else does).” Supreme Court Economic Review 3, no. 1 (1993): 1-41. https://doi.org/10.1086/scer.3.1147064

Ash, Elliott, Daniel L. Chen, and Suresh Naidu. “Ideas Have Consequences: The Impact of Law and Economics on American Justice.” The Quarterly Journal of Economics 141, no. 1 (2026): 845-887. https://doi.org/10.1093/qje/qjaf042

Glynn, Adam N., and Maya Sen. “Identifying Judicial Empathy: Does Having Daughters Cause Judges to Rule for Women’s Issues?” American Journal of Political Science 59, no. 1 (2015): 37-54. https://doi.org/10.1111/ajps.12118

Ash, Elliott, Sam Asher, Aditi Bhowmick, Sandeep Bhupatiraju, Daniel Chen, Tanaya Devi, Christoph Goessmann, Paul Novosad, and Bilal Siddiqi. “In-Group Bias in the Indian Judiciary: Evidence from 5 Million Criminal Cases.” The Review of Economics and Statistics (2025): 1-45. https://doi.org/10.1162/rest_a_01569

Choi, Donghyun Danny, J. Andrew Harris, and Fiona Shen-Bayh. “Ethnic bias in judicial decision making: Evidence from criminal appeals in Kenya.” American Political Science Review 116, no. 3 (2022): 1067-1080. https://doi.org/10.1017/S000305542100143X

Ash, Elliott, Daniel L. Chen, and Arianna Ornaghi. “Gender attitudes in the judiciary: Evidence from US circuit courts.” American Economic Journal: Applied Economics 16, no. 1 (2024): 314-350. https://doi.org/10.1257/app.20210435

Boyd, Christina L., Lee Epstein, and Andrew D. Martin. “Untangling the causal effects of sex on judging.” American Journal of Political Science 54, no. 2 (2010): 389-411. https://doi.org/10.1111/j.1540-5907.2010.00437.x

Spirig, Judith. “When Issue Salience Affects Adjudication: Evidence from Swiss Asylum Appeal Decisions.” American Journal of Political Science 67, no. 1 (2023): 55-70. https://doi.org/10.1111/ajps.12612

Miwa, Hirofumi. “Assessing the Conservative Nature of the Supreme Court of Japan via Ideal Point Estimation of Justices.” Journal of Empirical Legal Studies 22, no. 2 (2025): 186-215. https://doi.org/10.1111/jels.12411

Guthrie, Chris, Jeffrey J. Rachlinski, and Andrew J. Wistrich. “Inside the Judicial Mind.” Cornell Law Review 86, no. 4 (2001): 777-830. https://heinonline.org/HOL/P?h=hein.journals/clqv86&i=785