In the United States v. Macintosh case of 1930, the U.S. Supreme Court ruled that a person seeking naturalization as a U.S. citizen must be willing to take an unqualified oath of allegiance to support and defend the Constitution and laws of the United States against all enemies, foreign and domestic. The respondent in this case was a Canadian-born minister who had lived in America for many years but refused to pledge absolute obedience to American law on religious grounds, stating he would only obey those laws which did not conflict with his duty towards God's law. The court held that while freedom of belief is protected under First Amendment rights, when it comes to actions based on such beliefs - like refusing unconditional allegiance - they are subject to regulation by Congress for protection of society.

In the dissenting opinion for United States v. Macintosh, Justice Stone argued that the court majority had erred in its interpretation of the oath of allegiance required for naturalization. He contended that there was no legal basis to deny citizenship based on a person's unwillingness to engage in war except under direct command from God. The justice believed this decision violated religious freedom and personal conscience rights protected by the First Amendment. Furthermore, he pointed out inconsistencies with previous rulings where individuals were granted citizenship despite expressing reservations about participating in warfare due to religious beliefs or moral convictions. In his view, requiring absolute obedience to laws without considering one’s conscientious objections would undermine democratic principles and individual liberties fundamental to American society.