In the 1922 case of Keogh v. Chicago & Northwestern Railway Company, plaintiff John J. Keogh accused several railway companies of violating the Sherman Antitrust Act by conspiring to set freight rates at an artificially high level, causing him financial harm as a shipper. The Supreme Court ruled in favor of the defendants, stating that damages could not be awarded under antitrust laws for injuries caused by acts which are regulated and permitted under other federal statutes such as the Interstate Commerce Act (ICA). Since rate-setting was within the purview of ICA and overseen by Interstate Commerce Commission (ICC), it was immune from antitrust scrutiny unless ICC found them unreasonable or discriminatory but failed to act upon it. This ruling established what is known as "Keogh Doctrine", limiting private parties' ability to seek damages for alleged anti-competitive conduct when such conduct is regulated by another federal statute.

In the dissenting opinion for Keogh v. Chicago & Northwestern Railway Company et al., Justice Brandeis argued that the plaintiff, a shipper who alleged rate discrimination by railroads in violation of federal antitrust laws, should be allowed to seek damages. He disagreed with the majority's view that such claims were precluded because they would interfere with the regulatory authority of the Interstate Commerce Commission (ICC). According to Justice Brandeis, allowing shippers to sue under antitrust laws would not undermine ICC regulation but rather complement it by providing an additional enforcement mechanism against discriminatory practices. Furthermore, he contended that denying private remedies could leave victims without any recourse if regulators failed to act or their actions proved insufficient. Thus, he believed that both public and private enforcement were necessary for effective competition law.