After nearly a year of work, the Department of Justice’s Antitrust Division and the Federal Trade Commission last week released new horizontal merger guidelines. But along with the agencies’ self-congratulatory press releases came a biting public critique from FTC Commissioner J. Thomas Rosch.

The former Latham & Watkins partner, who is a Republican, called the guidelines “flawed” and of dubious value even as he concurred with their issuance.