Tyson Foods involved whether and how plaintiffs could use statistics in class actions. In doing so, the court relied on the amicus brief Zimmerman wrote with Professor Sergio Campus on behalf of complex litigation scholars. The brief explains the many ways statistics are used as evidence in complex litigation -- and cautions against a broad opinion barring their use. In its opinion, the majority cited the brief:
It follows that the Court would reach too far were it to establish general rules governing the use of statistical evidence, or so-called representative evidence, in all class action cases. Evidence of this type is used in various substantive realms of the law. Brief for Complex Litigation Law Professors as Amici Curiae 5–9; Brief for Economists et al. as Amici Curiae 8–10. Whether and when statistical evidence can be used to establish classwide liability will depend on the purpose for which the evidence is being introduced and on “the elements of the underlying cause of action,” Erica P. John Fund, Inc. v. Halliburton Co., 563 U. S. 804, 809 (2011)."Read the full brief below.