In the Brotherhood of Railroad Trainmen et al. v. Jacksonville Terminal Co., 1968, the U.S Supreme Court ruled in favor of labor unions' right to solicit members on railroad property. The case arose when a group of railroads sought an injunction against union solicitation on their premises, arguing that it violated their property rights and disrupted operations. However, the court held that under the Railway Labor Act (RLA), unions have a statutory right to organize workers for collective bargaining purposes and this includes soliciting membership from employees at their workplaces unless there is evidence showing substantial interference with normal railroad operations or other compelling reasons for prohibiting such activities. This decision upheld labor's freedom of association and reinforced protections for union organizing activity.

In the dissenting opinion for Brotherhood of Railroad Trainmen et al. v. Jacksonville Terminal Co., Justice Harlan, joined by Justices Stewart and White, argued that the majority's decision to allow union picketing at a railroad terminal violated principles of federalism and labor law precedent. He contended that this case should have been decided under state law rather than federal law because it involved trespassing on private property, which is traditionally a matter for states to regulate. Furthermore, he disagreed with the majority's interpretation of Railway Labor Act (RLA), arguing that it did not grant unions an absolute right to picket anywhere they chose without regard to property rights or other legal considerations. Instead, he believed that RLA only protected peaceful picketing in appropriate locations where workers had a legitimate interest in communicating their grievances.