Skip to main content

The Genealogy of Law

  • Tom S. Clark (a1) and Benjamin E. Lauderdale (a2)

Many theories of judicial politics have at their core the concepts of legal significance, doctrinal development and evolution, and the dynamics of precedent. Despite rigorous theoretical conceptualization, these concepts remain empirically elusive. We propose the use of a genealogical model (or “family tree”) to describe the Court's construction of precedent over time. We describe statistical assumptions that allow us to estimate this kind of structure using an original data set of citation counts between Supreme Court majority opinions. The genealogical model of doctrinal development provides a parsimonious description of the dependencies between opinions, while generating measures of legal significance and other related quantities. We employ these measures to evaluate the robustness of a recent finding concerning the relationship between ideological homogeneity within majority coalitions and the legal impact of Court decisions.

    • Send article to Kindle

      To send this article to your Kindle, first ensure is added to your Approved Personal Document E-mail List under your Personal Document Settings on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part of your Kindle email address below. Find out more about sending to your Kindle. Find out more about sending to your Kindle.

      Note you can select to send to either the or variations. ‘’ emails are free but can only be sent to your device when it is connected to wi-fi. ‘’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.

      Find out more about the Kindle Personal Document Service.

      The Genealogy of Law
      Available formats
      Send article to Dropbox

      To send this article to your Dropbox account, please select one or more formats and confirm that you agree to abide by our usage policies. If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your <service> account. Find out more about sending content to Dropbox.

      The Genealogy of Law
      Available formats
      Send article to Google Drive

      To send this article to your Google Drive account, please select one or more formats and confirm that you agree to abide by our usage policies. If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your <service> account. Find out more about sending content to Google Drive.

      The Genealogy of Law
      Available formats
Corresponding author
e-mail: (corresponding author)
Hide All

Authors' note: We thank Brandon Bartels, Barry Friedman, John Kastellec, Drew Linzer, and Jeff Staton for helpful comments and suggestions. We also thank Josh Strayhorn for helpful research assistance. This research was supported by the National Science Foundation (SES-0961058).

Hide All
Bailey, Michael A., and Maltzman, Forrest. 2011. The constrained court: Law, politics, and the decisions justices make. Princeton, NJ: Princeton University Press.
Bartels, Brandon L. 2009. The constraining capacity of legal doctrine on the U.S. Supreme Court. American Political Science Review 103(3): 474–95.
Benesh, Sara C. 2002. The U.S. Court of Appeals and the law of confessions: Perspectives on the hierarchy of justice. New York: LFB Scholarly Publishing.
Biskupic, Joan, and Witt, Elder. 1997. Congressional Quarterly's guide to the U.S. Supreme Court, 3rd ed. Washington, DC: Congressional Quarterly Press.
Blei, David M., Ng, Andrew Y., and Jordan, Michael I. 2003. Latent dirichlet allocation. Journal of Machine Learning Research 2003(3): 9931022.
Bommarito, Michael J., Katz, Daniel Martin, Zelner, Jon, and Fowler, James H. 2010. Distance measures for dynamic citation models. Physica 389(19): 4201–8.
Bueno de Mesquita, Ethan, and Matthew Stephenson. 2002. Informative precedent and intrajudicial communication. American Political Science Review 96(4): 112.
Carrubba, Clifford J., and Clark, Tom S. Forthcoming. Rule Creation in a Political Hierarchy. American Political Science Review.
Clark, Tom S., and Lauderdale, Benjamin. 2010. Locating Supreme Court opinions in doctrine space. American Journal of Political Science 54(4): 871–90.
Clark, Tom S., and Lauderdale, Benjamin. 2012. Replication data for: The Genealogy of Law.
Clark, Tom S., and Carrubba, Clifford J. 2012. A Theory of Opinion Writing in the Judicial Hierarchy. Journal of Politics 74(2): 584603.
Epstein, Lee, and Segal, Jeffrey A. 2000. Measuring issue salience. American Journal of Political Science 44(1): 6683.
Fowler, James H., and Jeon, Sangick. 2008. The authority of Supreme Court precedent: A network analysis. Social Networks 30(1): 1630.
Fowler, James H., Johnston, Timothy R., Spriggs, James F. II, Jeon, Sangick, and Wahlbeck, Paul J. 2007. Network analysis and the law: Measuring the legal importance of precedents at the U.S. Supreme Court. Political Analysis 15(3): 324–46.
Friedman, Barry. 2006. Taking law seriously. Perspectives on Politics 4(2): 261–76.
Gennaioli, Nicola, and Shleifer, Andrei. 2007. The evolution of common law. Journal of Political Economy 115(1): 4368.
George, Tracey E., and Epstein, Lee. 1992. On the nature of Supreme Court decision making. American Political Science Review 86: 323–37.
Hall, Kermit L. 1999. The Oxford guide to United States Supreme Court decisions. New York: Oxford University Press.
Hansford, Thomas G., and Spriggs, James F. II. 2006. The politics of precedent on the U.S. Supreme Court. Princeton, NJ: Princeton University Press.
Ignagni, Joseph A. 1994. Explaining and predicting Supreme Court decision making: The Burger Court's establishment clause decisions. Journal of Church and State 36(2): 301–21.
Kastellec, Jonathan P. 2010. The statistical analysis of judicial decisions and legal rules with classification trees. Journal of Empirical Legal Studies 7(2): 202–30.
Kornhauser, Lewis A. 1992a. Modeling collegial courts II: Legal doctrine. Journal of Law, Economics & Organization 8: 441–70.
Kornhauser, Lewis A. 1992b. Modeling collegial courts I: Path dependence. International Review of Law and Economics 12: 169–85.
Kort, Fred. 1957. Predicting Supreme Court decisions mathematically: A quantitative analysis of the “right to counsel” cases. American Political Science Review 51(1): 112.
Kritzer, Herbert M., and Richards, Mark J. 2002. Deciding the Supreme Court's administrative law cases: Does chevron matter? Paper prepared for the Annual Meeting of the American Political Science Association.
Lax, Jeffrey R., and Rader, Kelly T. 2009. Legal constraints on Supreme Court decision making: Do jurisprudential regimes exist? Journal of Politics 72(2): 273–84.
Lax, Jeffrey R. 2007. Constructing legal rules on appellate courts. American Political Science Review 101(3): 591604.
Lax, Jeffrey R. 2011. The new judicial politics of legal doctrine. Annual Review of Political Science 14: 131157.
Levi, Edward. 1949. An introduction to legal reasoning. Chicago: University of Chicago Press.
Maltzman, Forrest, Spriggs, James F. II, and Wahlbeck, Paul J. 2000. Crafting law on the Supreme Court: The collegial game. New York: Cambridge University Press.
Maltz, Earl M. 2000. The function of Supreme Court opinions. Houston Law Review 37: 1395–420.
Martin, Andrew D., and Quinn, Kevin M. 2002. Dynamic ideal point estimation via Markov Chain Monte Carlo for the U.S. Supreme Court, 1953-1999. Political Analysis 10(2): 134–53.
McGuire, Kevin T., and Vanberg, Georg. 2005. Mapping the policies of the U.S. Supreme Court: Data, opinions, and constitutional law. September 1-5.
McGuire, Kevin T. 1990. Obscenity, libertarian values, and decision making in the Supreme Court. American Politics Quarterly 18(1): 4767.
Patterson, Edwin W. 1951. The case method in American legal education: Its origins and objectives. Journal of Legal Education 4(1): 124.
Porter, Mason A., Onnela, Jukka-Pekka, and Mucha, Peter J. 2009. Communities in networks. Notices of the American Mathematical Society 56(9): 1082–97.
Quinn, Kevin M., Monroe, Burt L., Colaresi, Michael, Crespin, Michael H., and Radev, Dragomir R. 2010. How to analyze political attention with minimal assumptions and costs. American Journal of Political Science 54(1): 209–28.
Richards, Mark J., and Kritzer, Herbert M. 2002. Jurisprudential regimes in Supreme Court decision making. American Political Science Review 96(2): 305–20.
Segal, Jeffrey A. 1984. Predicting Supreme Court cases probabilistically: The search and seizure cases, 1962-1981. American Political Science Review 78(4): 891900.
Songer, Donald R., and Haire, Susan B. 1992. Integrating alternative approaches to the study of judicial voting: Obscentity cases in the U.S. Courts of Appeals. American Journal of Political Science 36: 963–82.
Spaeth, Harold J., Epstein, Lee, Ruger, Theodore W., Whittington, Keith E., Segal, Jeffrey A., and Martin, Andrew D. 2010. The Supreme Court database.
Spriggs, James F. II, and Hansford, Thomas. 2000. Measuring legal change: The reliability and validity of Shepard's citations. Political Research Quarterly 53(2): 327–41.
Staudt, Nancy, Friedman, Barry, and Epstein, Lee. 2007. On the role of ideological homogeneity in generating consequential constitutional decisions. North Carolina Law Review 86(5): 1299–332.
Sulam, Ian. 2011. Policy, precedent, indeterminacy: Using doctrine space to bridge across circuits. Paper presented at the Annual Meeting of the Midwest Political Science Association, Chicago, IL.
Recommend this journal

Email your librarian or administrator to recommend adding this journal to your organisation's collection.

Political Analysis
  • ISSN: 1047-1987
  • EISSN: 1476-4989
  • URL: /core/journals/political-analysis
Please enter your name
Please enter a valid email address
Who would you like to send this to? *


Altmetric attention score

Full text views

Total number of HTML views: 0
Total number of PDF views: 0 *
Loading metrics...

Abstract views

Total abstract views: 0 *
Loading metrics...

* Views captured on Cambridge Core between <date>. This data will be updated every 24 hours.

Usage data cannot currently be displayed