Experimental Evidence Related to Diversity Jurisdiction's Assumptions

While first-year law students are taught that the most common justification for federal diversity jurisdiction involves concerns about potential bias against out-of-state litigants in state courts, empirical attention to whether these bias concerns are warranted is comparatively underdeveloped.

In Diversity Jurisdiction and Out-of-State Bias: Experimental Evidence, Daniel Klerman (USC) and Jonathan Nash (Emory) report results from experiments designed to detect out-of-state bias. What they find, at bottom, is that their results do not “provide uniformly solid evidence for the existence of bias or of federal courts (at least as they are currently constituted) reducing that bias through the policing of lawyer appeals to bias.” The paper's abstract follows.

In Memoriam: Marc Galanter (1931-2026)

It is with sadness that I note the recent passing of Prof. Marc Galanter (Wisc.). As Brian Leiter observes (here), Professor Galanter's scholarly influence runs exceptionally deep. Marc, emeritus at the University of Wisconsin at Madison, where he had taught since the late 1970s, is wide recognized as "one of the most important figures in law & society scholarship over the past half-century." Colleagues at Wisconsin note that Marc's scholarly focus engages with, in part, "how the legal system, in the U.S. and elsewhere, actually functions in practice. While there are many people who embody our Law in Action tradition, it’s hard to think of a better exemplar." Finally, as a co-editor of the Journal of Empirical Legal Studies (JELS), I note that Marc's canonical contribution to volume 1:3 (2004), The Vanishing Trial: An Examination of Trials and Related Matters in Federal and State Courts, endures as one of JELS' most cited papers.

Data on Plea Offers & Implications for the "Trial Penalty" Hypothesis

While plea offers (and acceptances) are ubiquitous in our criminal justice system, empirical research on the plea bargaining process remains sparse. A recent paper by David Abrams (Penn.) et al., A (Plea) Offer You Can Refuse, sheds interesting and important new empirical light on a practice largely shrouded in secrecy.

The data encompass information on initial plea offers made for felonies between 2012 and 2017 in Philadelphia, and include initial plea offers for 87.4% of cases. These plea data are supplemented by additional data from the Administrative Office of Pennsylvania Courts as well as the Philadelphia Police Dept. The paper draws defendant-case level data from Philadelphia largely because, as the authors note, "it is the only large jurisdiction that has shared information on all plea offers – both those that are accepted and rejected – for a large number of cases." These data are pressed into the service of exploring the prevailing wisdom regarding the imposition of a "trial penalty" on defendants who reject plea offers.

The paper's core finding, implied in Figure 3 (below), surprises: "We find that initial plea offers are significantly longer than sentences for cases not immediately resolved through a plea, even when a person is later convicted at trial."

Figure 3. Plea offer and sentence length by method of case resolution, where defendant is guilty

 

What Contributes to Patent Opinions' Influence?

While scholarly efforts to explore reasons for a legal opinion's "influence" are long-standing, a recent paper takes a more focused approach. Specifically, in What Makes Federal Circuit Opinions Influential?, Jason Reinecke (Wisconsin) explores this question in the specific context of patent opinions and their influence at the Federal Circuit.

To be sure, debates on how to assess and operationalize "influence" in this context endure. While noting these debates, this paper settles on case citations as a "a common, useful, and reasonable metric to measure an opinion’s influence, even if imperfect."

Setting aside measurement error debates, the paper draws from a hand-coded dataset that includes "2,675 panel-level final written decisions and Rule 36 summary affirmances issued by the Federal Circuit between January 1, 2014, and May 31, 2021, that resulted in the disposition of at least one issue that could be classified as a pro-patentee ruling, a pro-challenger ruling, or a mixed ruling."

While the analyses are exclusively descriptive, two core findings emerge. First, and unsurprisingly, "some judges are more likely than others to issue binding opinions favoring patent owners (and others favoring patent challengers)." Second, and comparatively more surprising, the paper notes how similarly "mixed" panels "(i.e., panels with at least one pro-patentee judge and at least one pro-challenger judge) decide cases." The paper's abstract follows.

Save the Date: 2026 CELS

On behalf of the 2026 CELS co-organizers at Northwestern, Stephanie Didwania, Kyle Rozema, and David Schwartz, I am delighted to pass along the following information.

Save the Date!

Conference on Empirical Legal Studies

October 2-3, 2026

 The 20th Annual Conference on Empirical Legal Studies (CELS) will be held October 2-3, 2026 at Northwestern Pritzker School of Law in Chicago, Illinois.

 

More information here:

https://www.law.northwestern.edu/research-faculty/events/conferences/cels-2026/

 

CELS 2026 is co-sponsored by Northwestern Law and the Society for Empirical Legal Studies. 

2026 Northwestern Main and Advanced Causal Inference Workshops

A long-time colleague, Bernie Black (Northwestern), asked that I share the following information on his 2026 causal inference workshops.

We are excited to be holding our 15^th annual workshop on Research Design for Causal Inference at Northwestern Law School in Chicago, IL.  We invite you to attend. 

Main Workshop:  Monday – Friday, August 3 - August 7, 2026.

Advanced Workshop:  Monday – Wednesday, August 10-12, 2026.

Optional Machine Learning Primer:  Sunday afternoon, Aug. 9, 2026.

What is special about these workshops:

1.     World-class speakers working at the frontier of causal inference research.

2.     Stata and R Coding sessions with exclusive access to the dedicated repository.

3.     Breakout sessions for feedback on your own research.

In person-registration is limited to 125 participants for each workshop, so hurry up and register for in person attendance!

There will also be a Zoom option, but please come in person if you can.  We do our best, but the online experience is not the same.

For more conference and registration information: https://www.law.northwestern.edu/research-faculty/events/conferences/causalinference/