Empirical Research Methods in Law (5 ec)

Part of the Graduate School of Legal Studies. This course is designed to address the most important empirical research methods to law students, in a manner that will be fully accessible to those with no prior quantitative training or background in the subjects covered. No prior familiarity with statistics or empirical techniques is required.


Prof. dr. C.L.J. Caminada


Curriculum: Graduate School of Legal Studies
EC: 5
Level: 500
Year: Master / PhD-program
Term: 2nd semester
Block: 3
Language of instruction: English


Scholars recognize the value of empirical analysis in understanding the legal system and its role in society. Due to the information technology, data sources on the legal system are improving in quality and accessibility. Compared with just a few years ago, researchers today can easily access original data sets. However, empirical studies cover a range of techniques which are usually not sharply defined. Empirical research methods can be characterized by the collection of data and data-analyses on which a theory, hypotheses or conclusion is based. Several simple empirical tests are available to confront the best available data with theory.

In view of these developments, a working knowledge of empirical research methods ought to be among the professional tools of a well-trained attorney. An attorney, for example, trained in empirical methods will be more persuasive in the courtroom and the boardroom. Empirical training will also provide a better understanding of the statistical tools that experts will employ. Also, given the prevalence of empirical methods in the social sciences, anyone considering a career in academic research or in public interest or in policy work will be well served by acquiring some basic quantitative skills.

The emphasis in the course will be on equipping practitioners to be critical consumers of empirical material that may be used in legal cases and controversies and in the formation and evaluation of legislation. Another purpose of this course is to equip students with knowledge of various empirical research methods they could employ in their own research project. The knowledge will be both theoretical and practical.  The course will introduce students to such topics as survey research methodology, the design and conducting of experiments, data gathering and analysis through descriptive statistics, the use of (multiple) regression, why samples need to be taken in particular ways, how to perform simulations or cross-country data analyses, and more. In addition to discussing how to perform these techniques, we will also read cases and articles in which each of the techniques has figured. Students will fulfill the course requirements by writing a paper, by class participation, by presentation of their research to the class, and by completing several exercises.

Literature, Readings, and Webblog

  • David Cope, Fundamentals of Statistical Analysis, Foundation Press, 2005 (ISBN: 1587788950). A tiny textbook (109 pages) on the essentials of statistical analysis, especially written for smart people who are not especially comfortable with numbers (PhD students in Law). This book is developed to teach students with little or no quantitative background the fundamentals of statistics, and multiple regression analysis.
  • Reading list: assigned manuscripts, book and journal articles, cases, and other materials that are expected to be read. Reading material will be posted on the course website at Blackboard, which students should all be able to access using law school Westlaw passwords. The posted readings will also be hyperlinked off the Blackboard page of this course. Please check the Blackboard page regularly as materials will be add to the site during the course.
  • Empirical Legal Studies blog at . Note that quality of blogs may have a high variance. Researchers summarize interesting research, books, and new trends. There are, of course, other websites that cover topics of interest to those studying empirical research methods in law. For example we recommend Georgetown Law Library on Statistics & Empirical Legal Studies Research Guide, as this website will offer you selected publications in the discipline of empirical legal studies: .

Class Meetings, Assignments and Grading

  • Seminar: Number of (3 hour) seminars: 7
  • Required preparation by students: Reading material. Students are expected to actively engage in discussions with regard to the assignments.
  • Assignments: During the course, assignments have to be produced on a weekly basis. The indicated exercises will provide good checkpoints to judge the comprehension of the material.
  • Paper on research design: Participants are asked to prepare a short paper (5-6 A4) specifying the design of their research project. The research project should use empirical methods in law.

Students should attend every class. Course grades will be determined by five factors: class attendance, class participation, written assignments, an original paper, and a presentation of that paper to the class. The original paper will count for 40 percent of final grades; assignments 35 percent, the other factors will account for the remaining 25 percent. 

The volume of work that will be involved in the course - assignments on a weekly basis and completing the papers - is heavy. For that reason it is strongly recommended that students form teams of two people for the purposes of doing assignments, the paper, and the presentations. Nevertheless, students may choose to work alone. Members of the team will receive the same grade on team material, such as the paper, assignments and class presentations, but separate grades will be given to individual team members for the other components of the class. All assignments need to be submitted electronically (e-mail c.l.j.caminada@law.leidenuniv.nl) and has to be of professional quality. These assignments will be awarded with a grade. At least five assignments should be sufficient before students are allowed to deliver their (final) research project. Failure to submit assignments has as consequence that no exam grade will be calculated. Non-serious attempts at assignments (such to the judgment of the lecturer) will be understood as failure to submit. A late submission will automatically receive an insufficient.

Please note that there are two class dates in the schedule during which students will be expected to report on the progress in their project. Each team have to make a brief - roughly five-minute - presentation of the topic for its research project. Moreover, each team will describe its data-gathering efforts. That is, students will explain the data set they are using and how it helps to answer the questions they are investigating. These updates will not be graded. Empirical work requires regular progress. These are not projects that can be started and completed at the last minute. The updates are an opportunity for students to get feedback on their project. The last week of the course will be given over to presentations of papers. The presentations are expected to last, on average, 30 minutes and to be professional.

Goal and Background

The purpose of this course is to equip students with knowledge of various empirical research methods. Why is empirical research used (neglected) in a given research context? What methods with various pro’s and con’s may be deliberated then? The seminar exploits the device ‘learning by doing, and learning from each other’. The Graduate School of Legal Studies comprises students and PhD’s from widely varying background, ranging from masters in law to students at an undergraduate level. All participants are unfamiliar with empirical research. Therefore, the seminar Empirical Research Methods in Law is set up as an open discussion seminar, in which participants work together on mini research design problems. The supervisor starts each session with a short introduction, then small groups of students have to develop and specify a design for investigating a given research question. The designs developed in this way have to be presented to the other participants, who criticize and compare them with their own solution. This approach hopefully results in lively if not fierce discussions, and students get confronted with questions and solutions originating from quite different disciplines than their own. Research problems presented for solution are expected to be widely different, in such a way that various research methods (like observation, survey, interviews, experiments, cross country data …) are suggesting themselves. After a few meetings the course’s emphasis will be on the presentations and discussions of the research design of the participants themselves, even if these are at present in a relatively early, provisional stage.


Undergraduate level in Law. No prior familiarity with statistics or empirical techniques is required, however, it is recommended to complete an Introduction to Statistical Analysis prior to taking this course.  This course is not open for students with knowledge and skills in empirical research methods. It is recommended that these students participate in an individual track Empirical Research Design. Contact Koen Caminada prior to first class meeting: ++31 71 527 7858 or e-mail c.l.j.caminada@law.leidenuniv.nl.


  • Enrollment to the course via the Graduate School.
  • Due to the short time span of the course and the high intensity late entry can not be allowed.

Schedule Group 1

  1. Introduction: Why Empirical Research Methods in Law? (Tuesday 28-1-2014, 17-20 hrs)
  2. Reliability, Validity, and Descriptive Statistics (Tuesday 4-2-2014, 17-20 hrs)
  3. Tests of Statistical Significance, Correlation and Regression (Tuesday 11-2-2014, 17-20 hrs)
  4. Gathering Data and Sampling (Tuesday 18-2-2014, 17-20 hrs)
  5. Experiments and Writing about Numbers (Tuesday 25-2-2014, 17-20 hrs)
  6. Cross Country Data Analyses (Tuesday 11-3-2014, 17-20 hrs)
  7. Empirical Research Methods in Law in Action (Tuesday 18-3-2014, 17-20 hrs)
  8. Held in reserve (Tuesday 25-3-2014)
Rooms will be announced later.

Schedule Group 2

  1. Introduction: Why Empirical Research Methods in Law? (Friday 31-1-2014, 10-13 hrs)
  2. Reliability, Validity, and Descriptive Statistics (Friday 7-2-2014, 10-13 hrs)
  3. Tests of Statistical Significance, Correlation and Regression (Friday 14-2-2014, 10-13 hrs)
  4. Gathering Data and Sampling (Friday 21-2-2014, 10-13 hrs)
  5. Experiments and Writing about Numbers (Friday 28-2-2014, 10-13 hrs)
  6. Cross Country Data Analyses (Friday 14-3-2014, 10-13 hrs)
  7. Empirical Research Methods in Law in Action (Friday 21-3-2014, 10-13 hrs)
  8. Held in reserve (Friday 28-3-2014)
Rooms will be announced later.

Reading List

To be found at Blackboard.

Additional Course Material and Elective Themes

This is a basic course in Empirical Research Methods in Law. The course is not able to cover several topics in class sessions. Students are encouraged to work on elective themes by themselves. 

  • How to lie and cheat with statistics? “43 percent of people lie about statistics. 72 Percent know that.” Over the last fifty years, the famous book from Darrel Huff on “How to Lie with Statistics” has sold more copies than any other statistical text. More on this (websites and blogs):    

  • “An application for child support has been dismissed despite a blood test showing it is 99.8% probable that the man being sued is the father of a four-year old girl. (99.8% Probability).” Read more on Probability theory and Probability axioms via a free statistics textbook from Richard Lowry, Concepts and Applications of Inferential Statistics, “Chapter 6: Introduction to Probability Sampling Distributions”, 2006 (http://faculty.vassar.edu/lowry/webtext.html).  

  • Analytical Tools & Methods for Law. There are several textbooks for students with little or no quantitative background to the basic analytical techniques that attorneys need to master to represent their clients effectively. 

  • Discovering Statistics using SPSS. Read Andy Field's bestselling textbook for undergraduate social science students. The title of the book accurately reflects the approach taken. This is not simply a primer on how to use SPSS, but is a very good statistics text using SPSS as a vehicle for illustrating and expanding on the statistical content of the book. At the same time it also serves as a manual for SPSS. One advantage of the text is that it is not tied specifically to the latest version of SPSS. It provides students of statistical methods with everything they need to understand, use and report statistics - at every level. Written in Andy Field's vivid and entertaining style, and furnished with playful examples from everyday student life (among other places), the book forms an accessible gateway into the often intimidating world of statistics and a unique opportunity for students to ground their knowledge of statistics through the use of SPSS. The book provides support for those less confident about statistical analysis whilst having sufficient depth that it will still be valuable to more mathematically experienced people. There is a focus throughout on the practical aspects of data analysis and interpretation.
    Reference: Andy Field, Discovering Statistics Using SPSS, Sage Publications, 2005 (816 pages, ISBN: 9780761944522).  

  • Access and Reliability of Administrative Data. Some references:
    Theodore Eisenberg & Margo Schlanger, “The Reliability of the Administrative Office of the U.S. Courts Database: An Initial Empirical Analysis,” Notre Dame Law Review 78(5), 2002, pp. 1455-1496.
    Lynn M. LoPucki, “The Politics of Research Access to Federal Court Data,” Texas Law Review 80, 2002, pp. 2161-1271.

  • Simulations are imitations of the real world. This empirical tool can be helpful in legal research to understand certain key characteristics or behaviors of, for example, alternative (tax) rules or laws. Simulation is used in many contexts, including the of systems in order to gain insight into their functioning. Simulation can be used to show the effects of alternative conditions and causes of action. Key issues in simulation include acquisition of valid data source information about the system, a selection of key characteristics, the use of simplifying approximations and assumptions within the simulation, and reliability and validity of the simulation outcomes. See for applications of simulations in the research field of tax law and economics:
    Koen Caminada & Kees Goudswaard, “Does a Flat Rate Personal Income Tax Reduce Tax Progressivity? A Simulation for the Netherlands”, Public Finance & Management 1(4), 2001, pp. 471-500.
    Koen Caminada & Kees Goudswaard, “Progression and Revenue Effects of Income Tax Reform”, Internatio­nal Tax and Public Finance 3 (1), 1996, pp. 57‑66.
    Koen Caminada and Kees Goudswaard, 'Revenue Effects of Tax Facilities for Pension Savings', Atlantic Economic Journal 36 (2), 2008, pp. 233-246.

  • The  JELS  is a peer-edited, peer-refereed, interdisciplinary journal that publishes high-quality, empirically-oriented articles of interest to scholars in a diverse range of law and law-related fields, including civil justice, corporate law, criminal justice, domestic relations, economics, finance, health care, political science, psychology, public policy, securities regulation, and sociology.  There is currently a gap in the legal and social science literature that has often left scholars, lawyers, and policymakers without basic knowledge of legal systems or with false or distorted impressions. Even simple descriptive data about the functioning of courts and the legal systems are often lacking. Reform and intellectual debate have previously proceeded in an empirical vacuum. Courts and lawyers often do not know what to make of empirical findings in part because they so rarely encounter them. JELS fills this gap. Both experimental and non-experimental data analysis are welcome, as are law-related empirical studies from around the world. Website.

Last Modified: 30-07-2013