An atheist organization has filed suit against President Donald Trump and the Internal Revenue Service over the president’s “religious liberty” executive order, arguing that it’s unconstitutional government support for religious organizations.

The Freedom From Religion Foundation, headquartered in Wisconsin, filed the lawsuit Thursday in U.S. District Court, the Western District of Wisconsin. The action maintains that the president’s order would selectively benefit churches and religious organizations by allowing them to endorse political candidates without risking their tax-exempt status.

The intent of the president’s order is to weaken enforcement of the so-called Johnson Amendment, a 1954 law that restricts all tax-exempt institutions from campaigning for — or against — political candidates.

Trump’s executive order specifically refers to religions and religious organizations, and Trump pointedly spoke only of “people of faith” and religions in his remarks in the Rose Garden Thursday as he signed the order.

“This executive order directs the IRS not to unfairly target churches and religious organizations for political speech,” he said. “No one should be censoring sermons or targeting pastors. We are giving our churches their voices back.”

“Among its many faults,” the FFRF lawsuit states, Trump’s order “requires the IRS to selectively and preferentially discontinue enforcement of the electioneering restrictions of the tax code against churches and religious organizations, while applying a more vigorous enforcement standard to secular nonprofits.”

The FFRF suit contends the order violates its equal protection and free speech rights under the Constitution, and that favoring church groups over secular groups is in violation of the Establishment Clause of the First Amendment. The suit seeks an injunction preventing the IRS from implementing Trump’s order, and asks that the tax agency equitably enforce the electioneering restrictions against all tax-exempt organizations.

Trump vowed during his campaign to grant religious organizations influence in the political arena without having to give up their tax-exempt status. “I said for the evangelicals that we’re going to do something that nobody’s even tried to do,” Trump said at the GOP convention. “We put into the platform, we’re going to get rid of the horrible Johnson Amendment.”

New York Attorney General Eric Schneiderman on Thursday trolled Trump on Twitter following the president’s press conference touting that “religious discrimination” would no longer be tolerated in the U.S. Schneiderman reminded Trump that his two travel bans targeting Muslim nations have been blocked in court because of concerns about religious discrimination.

The American Civil Liberties Union has decided not to sue over the executive order — for now — after determining that it has no real legal clout and was little more than a “sop to religious conservatives,” according to a statement by ACLU executive director Anthony Romero.

We thought we'd have to sue Trump today. But it turned out the order signing was an elaborate photo-op with no discernible policy outcome. — ACLU National (@ACLU) May 4, 2017