In the case of United States v. Brooklyn Eastern District Terminal (1918), the Supreme Court ruled on a dispute involving federal regulation of interstate commerce and its application to intrastate activities. The Brooklyn Eastern District Terminal, a New York corporation, was engaged in transferring freight cars between railroads within New York City but also served as an essential link for interstate transportation. The Interstate Commerce Commission sought to regulate this activity under the Hepburn Act which extended federal control over terminal facilities involved in interstate trade. However, the company argued that since their operations were entirely within one state, they should not be subject to federal regulations. The Supreme Court disagreed with this argument and upheld the authority of Congress and by extension, regulatory bodies like ICC to oversee such activities even if they are geographically confined within one state's borders because these operations significantly affect interstate commerce. This decision reinforced Congressional power under the Commerce Clause of Constitution which allows it to regulate any commercial activity that has substantial impact on inter-state trade regardless of where it physically takes place.

In the dissenting opinion for United States v. Brooklyn Eastern District Terminal, Justice McReynolds disagreed with the majority's interpretation of the Employers' Liability Act. He argued that it was not Congress' intent to hold employers liable for injuries sustained by employees during their commute to and from work, as these activities were outside of their employment duties. According to him, such an expansive reading would lead to absurd results where employers could be held responsible for any harm or accident that befell workers on their way home or even while at home if they lived on company property. Furthermore, he contended that this broad liability would place an undue burden on interstate commerce companies who might have no control over conditions in areas surrounding their workplaces but could still be held accountable under this ruling.