The Future of Economics in Merger Trials : Rumors of its Demise are Greatly Exaggerated

From 2018 to 2020, the government suffered a string of defeats in antitrust merger trials. In each of those cases, a federal district court judge rejected the government plaintiffs’ claim that the transaction would harm competition in violation of Section 7 of the Clayton Act and thus declined to grant an injunction. The specific reasons for allowing the proposed transaction to proceed, as well as the underlying factual context, differed from case to case, but there is arguably at least one common thread: skepticism or outright hostility to the plaintiffs’ economic testimony. Some proponents of more vigorous antitrust enforcement that judges ask for too much from economics while at the same time giving the broader insights that economics can provide too little weight. We examine these cases from a slightly different perspective. Instead of considering whether they were rightly decided, or whether or how the law should change to compel (or allow) different outcomes, we ask what these cases tell us about what makes economic testimony compelling within the current legal framework