The Federal Trade Commission (FTC) on Friday urged a Washington, D.C. federal judge to reject Meta Platforms Inc.’s attempt to strike the testimony of the agency’s lead economics expert, dismissing Meta’s accusation of bias as unfounded and without legal merit.

In an opposition brief filed with the court, the FTC criticized Meta for avoiding the substantive issues of the case by launching “personal attacks and misdirection” against New York University School of Law professor C. Scott Hemphill, labeling him as a biased expert witness. The FTC emphasized that under the law, expert witnesses are not required to be entirely objective or disinterested, and that claims of bias are a matter for cross-examination, not exclusion.

Meta’s motion argued that Professor Hemphill improperly advocated for the FTC’s case, but the FTC responded that Hemphill had no involvement in the agency’s investigation or litigation until well after the lawsuit was filed. The FTC also pointed out that the motion to strike was untimely and prejudicial, as it missed the court’s deadline for pretrial motions.

The ongoing bench trial, presided over by U.S. District Judge James E. Boasberg, centers on the FTC’s allegations that Meta’s acquisitions of Instagram in 2012 and WhatsApp in 2014 were monopolistic efforts to eliminate competition in the personal social networking market. The FTC claims Meta holds a monopoly competing primarily with Snap and MeWe, while Meta argues it faces broad competition from platforms like TikTok and YouTube.

Professor Hemphill’s testimony addresses critical economic issues, including whether Meta paid a premium to acquire Instagram as a means to stifle a competitor or whether the price reflected legitimate value and uncertainty about Instagram’s future success. He also challenges Meta’s contention that users readily substitute between Meta platforms and competitors like TikTok.

Meta’s motion to strike also cited a 2019 presentation by Hemphill and former White House adviser Tim Wu urging stronger antitrust enforcement against Facebook, which the FTC counters was a single academic meeting unrelated to the investigation or litigation at the time.

Representing the FTC are in-house attorneys Daniel J. Matheson and Barrett J. Anderson. Meta is represented by Mark C. Hansen, Aaron M. Panner, Geoffrey M. Klineberg, Silvija A. Strikis, Andrew Skaras, and Zachary M. Meskell of Kellogg Hansen Todd Figel & Frederick PLLC.

The case, Federal Trade Commission v. Meta Platforms Inc., case number 1:20-cv-03590, is before the U.S. District Court for the District of Columbia.