by John Marshall Harlan, Adair v. United States — Opinion of the Court
“ As we all know, there are special labor unions of men engaged in the service of carriers. These unions exercise a direct influence upon the employment of labor in that business, upon the terms of such employment, and upon the business itself. Their very existence is directed specifically to the business, and their connection with it is, at least, as intimate and important as that of safety couplers, and, I should think, as the liability of master to servant,-matters which, it is admitted, Congress might regulate, so far as they concern commerce among the states. ”
