While the labor market implications of mergers have been historically ignored as "out of market" effects, recent actions by the Department of Justice (DOJ) place buyer market power (i.e., monopsony) at the forefront of antitrust policy. We develop a theory of multi-plant ownership and monopsony...

Antitrust enforcement in the United States has declined since the 1960s. Building on several new datasets, we argue that this decline did not reflect a popular demand for weaker enforcement or any other kind of democratic sanction. The decline was engineered by unelected regulators and judges...