Felix Frankfurter,
United States v. Congress of Industrial Organizations…
“ There can be little doubt of Congress' power to regulate the making of political contributions and expenditures by labor unions, as well as by other organizations and individuals, in the interest of free and pure elections and the prevention of official corruption, by appropriate measures not trenching on those basic rights. But when regulation or prohibition touches them, this Court is duty bound to examine the restrictions and to decide in its own independent judgment whether they are abridged within the Amendment's meaning. ”
