The U.S. Supreme Court case Atlantic Coast Line Railroad Co. et al. v. Brotherhood of Railway Trainmen et al., 1966, revolved around the issue of whether a federal court could enjoin a railroad labor union from encouraging its members to file claims for personal injuries under the Federal Employers' Liability Act (FELA). The plaintiffs, several railway companies, argued that such actions by the union constituted an illegal interference with their business operations and sought injunctive relief to stop it. However, in a unanimous decision delivered by Justice William O. Douglas, the Supreme Court held that federal courts lacked jurisdiction to grant such injunctions against unions under these circumstances due to Norris-LaGuardia Act which limits courts' power in issuing injunctions in cases involving labor disputes. The court reasoned that FELA was enacted specifically to protect railway workers’ rights and provide them with remedies for workplace injuries; thus any attempt by employers or courts to limit this right would be contrary to congressional intent behind FELA.

In the dissenting opinion for Atlantic Coast Line Railroad Co. et al. v. Brotherhood of Railway Trainmen et al., Justice Harlan disagreed with the majority's decision to allow a federal court to intervene in an ongoing labor dispute between a railroad company and its employees' union, arguing that it was not within their jurisdiction as per the Norris-LaGuardia Act (NLGA). He believed that this case should have been handled by National Railroad Adjustment Board (NRAB), which is specifically designed to handle such disputes under the Railway Labor Act (RLA). The NLGA restricts courts from issuing injunctions in labor disputes unless certain conditions are met, none of which were present here according to Justice Harlan. Furthermore, he argued that allowing judicial intervention undermines NRAB’s authority and could potentially disrupt future collective bargaining processes.