Circuit Split Grows over Whether Evidence Supportive of Class Certification Must be Admissible

Tager_09181Featured Expert Contributor, Judicial Gatekeeping of Expert Evidence

By Evan M. Tager, a Partner in the Washington, DC office of Mayer Brown LLP, with Carl J. Summers, Counsel with Mayer Brown LLP.

The Supreme Court explained in Wal-Mart Stores, Inc. v. Dukes that “Rule 23 does not set forth a mere pleading standard.  A party seeking class certification must affirmatively demonstrate his compliance with the Rule—that is, he must be prepared to prove that there are in fact sufficiently numerous parties, common questions of law or fact, etc.”  You would think that would mean that plaintiffs seeking class certification must support their motion with admissible evidence.  Indeed, in Dukes the Supreme Court observed that the district court had held that “Daubert did not apply to expert testimony at the certification stage of class-action proceedings” and commented: “We doubt that is so.”

Nevertheless, relying on a 1975 Ninth Circuit decision and a pre-Dukes decision of the Eighth Circuit, the Ninth Circuit recently held in Sali v. Corona Regional Medical Center that “[i]nadmissibility alone is not a proper basis to reject evidence submitted in support of class certification” and that a district court therefore abused its discretion by declining to consider a declaration “solely on the basis of inadmissibility.”  Continue reading “Circuit Split Grows over Whether Evidence Supportive of Class Certification Must be Admissible”