This statute also mandated loss of citizenship for desertion from the U.S. armed forces, remaining outside the United States in order to evade military service during wartime, or voting in a foreign election. The provision calling for loss of citizenship for foreign military service was held by the Supreme Court not to be enforceable without proof that said service had been voluntary, in a 1958 case ("Nishikawa v. Dulles"), and revocation of citizenship as a punishment for desertion was struck down that same year in another case ("Trop v. Dulles"). However, in yet another 1958 case ("Perez v. Brownell)," the Supreme Court affirmed the provision revoking the citizenship of any American who had voted in an election in a foreign country, as a legitimate exercise (under the Constitution's Necessary and Proper Clause) of Congress' authority to regulate foreign affairs and avoid potentially embarrassing diplomatic situations. Associate Justice Felix Frankfurter, the author of the opinion of the Court (supported by a 5–4 majority), wrote that:  In a dissenting opinion, Chief Justice Earl Warren argued that "Citizenship is man's basic right, for it is nothing less than the right to have rights" and that "a government of the people cannot take away their citizenship simply because one branch of that government can be said to have a conceivably rational basis for wanting to do so." While Warren was willing to allow for loss of citizenship as a result of foreign naturalization or other actions "by which [an American] manifests allegiance to a foreign state [which] may be so inconsistent with the retention of [U.S.] citizenship as to result in loss of that status", he wrote that "In specifying that any act of voting in a foreign political election results in loss of citizenship, Congress has employed a classification so broad that it encompasses conduct that fails to show a voluntary abandonment of American citizenship." Two Supreme Court decisions after "Perez" called into question the principle that loss of citizenship could occur even without the affected individual's intent. In "Kennedy v. Mendoza-Martinez" (1963), the Court struck down a law revoking citizenship for remaining outside the United States in order to avoid conscription into the armed forces. Associate Justice William J. Brennan (who had been in the majority in "Perez") wrote a separate opinion concurring with the majority in "Mendoza-Martinez" and expressing reservations about "Perez". In "Schneider v. Rusk" (1964), where the Court invalidated a provision revoking the citizenship of naturalized citizens who returned to live permanently in their countries of origin, Brennan recused himself and did not participate in the decision of the case.