The Johnson Amendment, a 1954 provision which prohibits churches and nonprofit groups from making public endorsements of political candidates, could be repealed through the tax reform bill currently in the US Senate.

The repeal was packaged into the bill which passed the House a few weeks ago, but has yet to be approved by the Senate. Congressional action is required to formally repeal the law.

As the Johnson Amendment currently stands, religious ministers, churches, and nonprofit charitable organizations are barred from engaging in political activity, including endorsing candidates, at the risk of losing their 501(c)(3) tax-exempt status.

The Johnson Amendment was named after then-Senator Lyndon B. Johnson and his re-election campaign in 1954. He wrapped the amendment into the tax code overhaul in order to ban nonprofit groups from engaging in political campaigns.

The repeal would overthrow the 63-year old amendment, and churches could begin receiving as much as $1.7 billion from donors each year — money that traditional political committees would normally receive, according to the New York Times.

Some of the repeal’s critics believe that the shift would create sham churches and increase the amount of untraceable political spending.

In addition, many religious groups, such as the United Methodist Church, the National Council of Churches and the Baptist Joint Committee for Religious Liberty are opposing the repeal, saying it could threaten the stability of the mission of religious croups.

However, other Christian groups have applauded the repeal, including the legal group Alliance Defending Freedom, who believes the current law suppresses free speech.

“The law has a chilling effect on free speech,” said Michael Farris, president of Alliance Defending Freedom, according to the New York Times.

The Senate will be voting this week on its own version of the tax bill, which does not currently include the Johnson Amendment reform.