The U.S. Supreme Court case International Association of Machinists et al. v. Street et al., 1960, revolved around the issue of union dues being used for political purposes against the will of certain members who disagreed with those politics. The plaintiffs were railway employees who argued that their First Amendment rights were violated by having a portion of their compulsory union dues spent on political causes they did not support. In its decision, the court held that while unions could collect fees from non-members to cover costs related to collective bargaining and maintaining labor peace (the so-called "agency shop" arrangement), it was unconstitutional for these funds to be used in furtherance of political or ideological causes without individual members' consent.

In the dissenting opinion for International Association of Machinists et al. v. Street et al., Justice Frankfurter, joined by Justices Harlan and Whittaker, argued that the majority's interpretation of the Railway Labor Act was incorrect. They contended that Congress intended to allow unions to use funds from all members for political purposes as a means of advancing collective bargaining goals. The dissenters believed this case should have been resolved on constitutional grounds rather than statutory ones; they felt it raised serious First Amendment issues regarding freedom of speech and association in relation to union activities funded by dues collected from non-consenting members. However, they also noted that these constitutional questions were not properly before the Court due to procedural reasons, suggesting a more appropriate resolution would be remanding back down for further proceedings.