Institutional Design and Antitrust Evidentiary Standards

The purpose of this paper is to study the relative impact of public and private competition law enforcement on antitrust liability. We develop a model with asymmetric information during trial, where the number of cases filed depends on the amount of damages awarded and on the standard of evidence applied either by the public authority or by the judge. Our model predicts that higher damages result in a higher standard of evidence, which is not always welfare improving. We also show that public enforcement better incentivizes pro-competitive practices by allowing a lower standard of evidence. This may lead the public enforcement to outperform the private enforcement.