Source: https://www.atheists.org/legal/faq/first-amendment/
Timestamp: 2019-04-23 00:47:49+00:00

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Is atheism protected under the First Amendment?
Yes. The First Amendment prohibits the government from punishing citizens for professing and exercising their religious beliefs—including a lack of religious belief. So how are atheists, who by definition do not have religious beliefs or exercise a religion, protected by the First Amendment?
First, atheists are protected by the Establishment Clause, which prohibits the government from establishing a government-sponsored house of worship or showing preference to one or all religions by passing laws to favor religion, or by forcing citizens to profess belief in religion or attend religious services.1 This protects atheists from being forced to participate in government-sponsored religion and from government reprisal if atheists did not participate.
Atheism is not a religion, but it does “take a position on religion, the existence and importance of a supreme being, and a code of ethics.”6 For that reason, it qualifies as a religion for the purpose of First Amendment protection, despite the fact that in common usage atheism would be considered the absence, rejection, or opposite of religion. Put another way, discrimination on the basis of religious belief extends to all beliefs about religion.
Though the Second Circuit ruled against the atheists’ RFRA claim, it is notable that the court was willing to entertain the challenge at all. Neither the Second Circuit nor the lower court which first dismissed the case questioned the ability of atheists to make a claim under RFRA.11 If this posture is followed by other courts, it would appear that atheism/secularism may be treated as the equivalent of religion in most legal disputes.
1 Everson v. Bd. of Educ., 330 U.S. 1, 15-16 (1947).
2 McCreary Cnty. v. ACLU, 545 U.S. 844, 875 (2005).
3 McCreary Cnty. v. ACLU, 545 U.S. 844, 884 (2005).
4 Torcaso v. Watkins, 367 U.S. 488, 495 n.11 (1961).
5 Wallace v. Jaffree, 472 U.S. 38, 52-53 (1985).
6 Kaufman v. McCaughtry, 419 F.3d 678, 682 (2005).
7 Burwell v. Hobby Lobby Stores, Inc., 573 U.S. __, 134 S. Ct. 2751 (2014).
8 Newdow v. Peterson, 753 F.3d 105 (2nd Cir. 2014).
9 Newdow v. Peterson, 753 F.3d 105 (2nd Cir. 2014).
10 Newdow v. Peterson, 753 F.3d 105 (2nd Cir. 2014).
11 Newdow v. United States, 2013 U.S. Dist. LEXIS 128367 (S.D.N.Y. Sept. 9, 2013).

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