In Zavada v. United States (1957), the petitioner, a naturalized U.S. citizen of Ukrainian origin, was accused by the government of illegally obtaining his citizenship through concealment and misrepresentation during his naturalization process in 1944. The Supreme Court had to decide whether or not to revoke Zavada's citizenship based on these allegations. The government claimed that he failed to disclose his membership in an organization advocating for the overthrow of the U.S Government - specifically, that he served as a secretary for this group from 1936-1938 before becoming a citizen. The court ruled against Zavada, deciding that there was enough evidence proving he deliberately concealed information about his past affiliations with such organizations during his naturalization proceedings which would have been grounds for denying him citizenship at that time if known. Therefore, it upheld the lower courts' decisions revoking Mr.Zavada’s American Citizenship due to fraudulent procurement.

In the dissenting opinion for Zavada v. United States, it was argued that the majority's decision to uphold Zavada's conviction under Section 2 of the Smith Act violated his First Amendment rights. The dissenting justices believed that there was insufficient evidence to prove that Zavada had advocated or taught the violent overthrow of government as required by statute. They also expressed concern about potential misuse and overreach of this law, arguing it could be used to suppress political dissidents who posed no real threat to national security. Furthermore, they disagreed with how broadly "advocacy" and "teaching" were interpreted in this case, suggesting such broad interpretations could lead to further erosion of free speech protections in future cases involving similar charges.