Numerous commentators have characterized the Roberts Court’s antitrust decisions as radical departures that betray a pro-business, anticonsumer bias. That characterization is inaccurate. Although some of the decisions do represent significant changes from past practice, the “pro-business/anti-consumer” characterization fails to appreciate the fundamental limits of antitrust, a body of law that requires judges and juries to make fine distinctions between procompetitive and anticompetitive behaviors that frequently resemble each other. Although false acquittals of anticompetitive conduct may harm consumers, so may false convictions of procompetitive actions. And efforts to eliminate errors in liability judgments are themselves costly. Optimal...