In United States v. Robel, the Supreme Court ruled that a provision of the Subversive Activities Control Act of 1950 was unconstitutional as it violated First Amendment rights to freedom of association and Fifth Amendment due process protections. The case involved Robert A. Robel, an employee at a defense facility who was also a member of the Communist Party USA. Under Section 5(a)(1)(D) of the Act, his membership in such organization made him ineligible for employment in any defense facility. The court held that this restriction was overly broad and infringed upon constitutionally protected freedoms without sufficient justification related to national security interests.

In the dissenting opinion for United States v. Robel, Justice White argued that the majority's decision was too broad and could potentially undermine national security efforts during times of war or emergency. He contended that Congress had a legitimate interest in preventing potential subversive activities by those employed in defense facilities and believed it was reasonable to restrict their employment based on membership in certain organizations deemed as risks to national security. While acknowledging concerns about First Amendment rights, he maintained that these restrictions were not absolute and should be balanced against other compelling interests such as national security. Furthermore, he criticized the majority for failing to provide clear guidelines on how far Congress could go in imposing such restrictions without violating constitutional rights.