In the United States v. Bethlehem Steel Company case of 1921, the U.S. Supreme Court ruled in favor of Bethlehem Steel Corporation against allegations made by the federal government that it had violated antitrust laws. The government accused Bethlehem Steel and other steel manufacturers of colluding to fix prices and control market shares, which would have been a violation of Sherman Antitrust Act. However, after examining evidence presented during trial proceedings, Justice Mahlon Pitney concluded that there was insufficient proof to substantiate these claims. He noted that while some actions taken by the companies might appear suspicious when viewed individually, they did not necessarily indicate an illegal conspiracy when considered as part of broader business practices within industry norms at that time.

In the dissenting opinion for United States v. Bethlehem Steel Company, Justice McReynolds disagreed with the majority's decision to uphold a lower court ruling that allowed Bethlehem Steel and other companies to purchase and control Midvale Steel & Ordnance Co., arguing it violated antitrust laws. He believed this acquisition would create an unfair monopoly in the steel industry, stifling competition and harming consumers through higher prices or reduced quality of goods. Furthermore, he argued that such consolidation could potentially lead to corruption as large corporations gain more power over markets and politics. His main concern was preserving free market principles by preventing monopolistic practices which can distort economic dynamics.