In the 20th century, the United States began to invalidate laws against blasphemy which had been on the books since before the founding of the nation ^{[citation needed]}, or prosecutions on that ground, as it was decided that they violated the American Constitution. The First Amendment to the United States Constitution provides that "Congress shall make no law respecting an establishment of religion, or prohibiting the free exercise thereof; or abridging the freedom of speech, or of the press...", and these restrictions were extended to state and local governments in the early 20th century. While there are no federal laws which forbid "religious insult" or "hate speech", some states continue to have blasphemy statutes.

In 2009, The New York Times reported that Massachusetts, Michigan, Oklahoma, South Carolina, Wyoming, and Pennsylvania had laws that made reference to blasphemy.^[1] Pennsylvania's blasphemy law was found unconstitutional in 2010.^[2] Some U.S. states still have blasphemy laws on the books from the founding days.

For example, Chapter 272 of the Massachusetts General Laws – a provision based on a similar colonial-era Massachusetts Bay statute enacted in 1697 – states:

Section 36. Whoever willfully blasphemes the holy name of God by denying, cursing or contumeliously reproaching God, His creation, government or final judging of the world, or by cursing or contumeliously reproaching Jesus Christ or the Holy Ghost, or by cursing or contumeliously reproaching or exposing to contempt and ridicule, the holy word of God contained in the holy scriptures shall be punished by imprisonment in jail for not more than one year or by a fine of not more than three hundred dollars, and may also be bound to good behavior.

The history of Maryland's blasphemy statutes suggests that even into the 1930s, the First Amendment was not recognized as preventing states from passing such laws. An 1879 codification of Maryland statutes prohibited blasphemy:

Art. 72, sec. 189. If any person, by writing or speaking, shall blaspheme or curse God, or shall write or utter any profane words of and concerning our Saviour, Jesus Christ, or of and concerning the Trinity, or any of the persons thereof, he shall, on conviction, be fined not more than one hundred dollars, or imprisoned not more than six months, or both fined and imprisoned as aforesaid, at the discretion of the court.

According to the marginalia, this statute was adopted in 1819, and a similar law dates back to 1723. In 1904, the statute was still on the books at Art. 27, sec. 20, unaltered in text. As late as 1939, this statute was still the law of Maryland. But in 1972, in Maryland v. Irving K. West, the Maryland Court of Appeals (the state's highest court) declared the blasphemy law unconstitutional.^[3] This law was repealed by the acts of 2002 effective as of October 1, 2002.

Maine's law reads as follows:

Blasphemy may be committed either by using profanely insolent and reproachful language against God, or by contumeliously reproaching Him, His creation, government, final judgment of the world, Jesus Christ, the Holy Ghost, or the Holy Scriptures as contained in the canonical books of the Old and New Testament, or by exposing any of these enumerated Beings or Scriptures to contempt and ridicule, and it is not necessary for the state to prove the doing of all of them.^[4]

Michigan's law reads as follows:

750.102 Blasphemy; punishment.

Sec. 102.

Punishment—Any person who shall wilfully blaspheme the holy name of God, by cursing or contumeliously reproaching God, shall be guilty of a misdemeanor.

History: 1931, Act 328, Eff. Sept. 18, 1931 ; CL 1948, 750.102 Former Law: See section 17 of Ch. 158 of R.S. 1846, being CL 1857, §5872; CL 1871, §7707; How., §9293; CL 1897, §11706; CL 1915, §15480; and CL 1929, § 16832.^[5]

Secondarily, there is an "anti-profanity" law, which includes "blasphemy" elements, and reads as follows.

750.103 Cursing and swearing.

Sec. 103.

Cursing and swearing—Any person who has arrived at the age of discretion, who shall profanely curse or damn or swear by the name of God, Jesus Christ or the Holy Ghost, shall be guilty of a misdemeanor. No such prosecution shall be sustained unless it shall be commenced within 5 days after the commission of such offense.

History: 1931, Act 328, Eff. Sept. 18, 1931 ; CL 1948, 750.103 Former Law: See section 18 of Ch. 158 of R.S. 1846, being CL 1857, §5873; CL 1871, §7708; How., §9294; CL 1897, §11707; CL 1915, §15481; and CL 1929, § 16833.^[6]

The last person to be jailed in the United States for blasphemy was Abner Kneeland in 1838 (a Massachusetts case: Commonwealth v. Kneeland).^{[contradictory][7]} From 1925, the Supreme Court applied the Bill of Rights to all states.^[8]

In February 1926, Lithuanian-American Communist Anthony Bimba was charged in Brockton, Massachusetts with blasphemy under a law passed during the time of the Salem Witch Trials more than two centuries earlier, as well as sedition.^[9] A widely publicized week-long trial followed, during which Bimba's attorney likened atheism to religious belief and maintained that individuals had a right under the United States constitution to believe or disbelieve in the existence of a God.^[10] Bimba was ultimately found not guilty of blasphemy but convicted of sedition, for which he was fined $100.^[11]

In 1921, Lithuanian-American Michael X. Mockus was convicted in Maine. He appealed to the Supreme Judicial Court of Maine on March 25, 1921 in State v. Mockus and lost the appeal.^[12]

The last known U.S. conviction for blasphemy was of atheist activist Charles Lee Smith. In 1928, he rented a storefront in Little Rock, Arkansas, and gave out free atheist literature there. The sign in the window read: "Evolution Is True. The Bible's a Lie. God's a Ghost." For this he was charged with violating the city ordinance against blasphemy. Because he was an atheist and therefore could not swear the court's religious oath to tell the truth, he was not permitted to testify in his own defense. The judge then dismissed the original charge, replacing it with one of distributing obscene, slanderous, or scurrilous literature. Smith was convicted, fined $25, and served most of a twenty-six-day jail sentence. His high-profile fast while behind bars drew national media attention. Upon his release, he immediately resumed his atheist activities, was again charged with blasphemy, and this time the charge held. In his trial he was again denied the right to testify and was sentenced to ninety days in jail and a fine of $100. Released on $1,000 bail, Smith appealed the verdict. The case then dragged on for several years until it was finally dismissed.^[13]

The U.S. Supreme Court in Joseph Burstyn, Inc. v. Wilson, 343 U.S. 495 (1952) held that the New York State blasphemy law was an unconstitutional prior restraint on freedom of speech. The court stated that "It is not the business of government in our nation to suppress real or imagined attacks upon a particular religious doctrine, whether they appear in publications, speeches or motion pictures."

The Pennsylvania General Assembly enacted a blasphemy law in 1977,^[14] that forbade corporations from incorporating names containing words that "constitute blasphemy, profane cursing or swearing, or that profane the Lord's name." In 2007, filmmaker George Kalman had filed a limited liability company named I Choose Hell Productions, LLC.^[15] A week later he had received an unsigned letter explaining that his application was rejected because his company's name could not "contain words that constitute blasphemy." In February 2009, Kalman filed suit to have the provision against blasphemy struck down as unconstitutional. During the trial, Kalman explained that at one point he had become suicidal and felt he had to choose between death and hell.^[16] This became the inspiration for naming his film company, stories that he would tell about how to choose life. On June 30, 2010, U.S. District Judge Michael M. Bayslon of the Eastern District of Pennsylvania, in a 68-page opinion, ruled in favor of Kalman, finding that Pennsylvania's blasphemy statute violated both the Establishment Clause and the Free Exercise Clause of the First Amendment to the United States Constitution.^{[17] [18]}

• Schroeder, Theodore (1919). Constitutional Free Speech Defined and Defended in an Unfinished Argument in a Case of Blasphemy. New York: Free Speech League.
• Barringer Gordon, Sarah (December 2010). "Blasphemy and the Law of Religious Liberty in Nineteenth-Century America". American Quarterly. 52 (4): 682–719. JSTOR 30042200.
• For a history of blasphemy laws in the United States, see amicus brief, filed 12/24/09 for Case No. 2:09-cv-00684 in Kalman v. Cortes, 723 F. Supp. 2d 766.