"a religious one or is a bona fide object of charity or philanthropy" and whether the solicitation "conforms to reasonable standards of efficiency and integrity."
Upon determination of the cause's legitimacy, a solicitation certificate would be issued.
Newton Cantwell and his two sons, Jesse and Russel, were Jehovah's Witnesses who were proselytizing in a heavily-Roman Catholic neighborhood in New Haven, Connecticut. The Cantwells were going door to door, with books and pamphlets and a portable phonograph with sets of records. Each record contained a description of one of the books. One such book was "Enemies", which was an attack on organized religion in general and especially the Roman Catholic Church. The two citizens who heard the record were incensed; though they wanted physically to assault the Cantwells, they restrained themselves.
The Cantwells said they did not get a license because they did not believe the government had the right to determine whether the Witnesses were a religion. They maintained the statute denied the trio their due process rights under the 14th Amendment, and it also denied them their freedom of speech and religious expression.
The Connecticut Supreme Court upheld the conviction of all three on the statutory charge and affirmed one son's conviction of breach of the peace, but remanded the breach of peace charge against the other two for a new trial.
The Court found that Cantwell's action was protected by the First and Fourteenth Amendments.
Justice Owen Roberts wrote in a unanimous opinion that "to condition the solicitation of aid for the perpetuation of religious views or systems upon a license, the grant of which rests in the exercise of a determination by state authority as to what is a religious cause, is to lay a forbidden burden upon the exercise of liberty protected by the Constitution."
This case incorporated (enforced) the First Amendment's Free Exercise Clause against the states, thereby protecting free exercise of religion from intrusive state action. The Establishment Clause was incorporated seven years later in Everson v. Board of Education (1947).
The Cantwell decision also marked the first time the U.S. Supreme Court incorporated the free exercise clause into the 14th Amendment, something it would do from that time forward.