President Trump signs an executive order aimed at easing an IRS rule limiting political activity for religious organizations on May 4 in the Rose Garden of the White House. (Evan Vucci/AP)

Lawmakers appear to be using a new spending bill to target a 1950s law that effectively bars nonprofits like churches from endorsing or opposing political candidates.

Many pastors already ignore the so-called Johnson Amendment, and the IRS rarely investigates churches that violate a law that many clergy feel provides a chilling effect on their free speech. But some observers fear the language proposed in a new spending bill released this week would make it difficult for the IRS to investigate any claims of pulpit politicking or money flowing between houses of worship and political campaigns.

During his campaign for the presidency, Donald Trump targeted the Johnson Amendment as a big part of his pitch to religious conservatives, but because the amendment is law, repealing it would take an act of Congress.

Instead of trying to repeal the amendment, legislators appear to be targeting it through a spending bill that says the IRS can’t use funds to investigate a church for breach of the Johnson Amendment without the sign-off of the IRS commissioner, who must report to Congress on the investigation. On Thursday, the House Appropriations Committee voted 28-24 to to keep language from Section 116 in a funding bill.

The language in the bill is clearly an effort to gut the Johnson Amendment as applied to churches, said Charles Haynes, a religious freedom expert at the Newseum.

“At the very least, this provision puts a further chilling effect on any attempts by IRS staff to enforce the Johnson Amendment with respect to pulpit speech — the part of the amendment that conservative churches have most opposed,” Haynes said. “At its worst, the provision keeps IRS staff from doing its job to prevent charitable donations to flow to political campaigns.”

Several religious groups this week sent a letter that voiced opposition to the measure to Rep. Tom Graves (R.-Ga.), chairman of the House appropriations subcommittee on financial services and general government, and ranking Democrat Rep. Mike Quigley (Ill.).

“Weakening current law would allow politicians and others seeking political power to pressure churches for endorsements, dividing congregations and opening them up to the flow of secret money,” the letter from about 40 organizations states. The Episcopal Church, the American Jewish Committee, the Evangelical Lutheran Church in America and the Baptist Joint Committee for Religious Liberty are among the groups listed on the letter.

If this measure is enacted, Melissa Rogers, a nonresident senior fellow at the Brookings Institution, believes Congress could possibly block decisions on a church’s tax-exempt status.

“If this measure is enacted, officeholders might find ways to subtly pressure houses of worship (by delaying grants of zoning permits, for example) until endorsements are made,” she said. “That’s illegal, but it could be hard to stop if measures like this one are enacted.”

Since taking office, President Trump has continued to oppose the Johnson Amendment. He focused on the law during his speech at the National Prayer Breakfast in February. In April, he signed an executive order in front of several high-profile religious leaders, but many religious freedom advocates were disappointed in the order, saying it didn’t go far enough.

The Johnson Amendment prohibits any nonprofit group from endorsing candidates, but the provision in the spending bill focuses specifically on religious organizations.

“Provisions, like this one, that give religious organizations special tax benefits and privileges that are unavailable to other nonprofits raise serious constitutional concerns,” said Daniel Mach, director of the ACLU Program on Freedom of Religion and Belief. The First Amendment, he says, bars the government from favoring religious viewpoints when handing out tax subsidies and benefits.

But Kim Colby, director of the Center for Law & Religious Freedom, says that the provision would make it clear that the IRS commissioner is the person who decides that a church should lose its tax-exempt status over political activity.

“This type of accountability is needed given that it is very possible that administrations could pick and choose which churches to deny tax-exempt status based on whether a church is perceived to be supportive of the policies of a Democratic administration or a Republican administration,” Colby said.

Churches are able to engage in political activity like voter engagement and individual clergy endorsements, but the Johnson Amendment bars endorsements from the pulpit. Many pastors have ignored the law, and many have made an explicit effort to challenge the law under a campaign called Pulpit Freedom Sunday. Thousands of churches have participated, and the IRS audited one but did not punish the church, according to the group that organizes the annual effort.

In the 1990s, a church lost its tax-exempt status after taking out a full-page ad against then-President Bill Clinton in USA Today. But generally, the IRS does not investigate churches over politicking, something religious conservatives have been frustrated by since Lyndon B. Johnson introduced the legislation in the Senate in 1954, when he was a senator from Texas.

Americans are almost evenly divided on whether churches and other houses of worship should express their views on social and political matters, according to a 2016 Pew Research Center survey. But 66 percent opposed the idea of churches endorsing candidates.

This piece has been updated.