A group of clergy filed a complaint Monday with the Internal Revenue Service to block a conservative legal group from organizing pastors willing to risk their church’s tax-exempt status to preach about politics.

The group, backed by three former top IRS officials, contends that pastors should respect the 54-year-old rule of law that bans tax-exempt houses of worship from endorsing political candidates. They call on the IRS to examine if organizer Alliance Defense Fund has violated its own tax-exempt status by encouraging pastors to make political endorsements from their pulpit.

"As religious leaders, we have grave concerns about the ethical implications of soliciting and organizing churches to violate core principles of our society," the 55 Christian and Jewish leaders wrote in their claim, according to The Washington Post.

The two Ohio pastors organizing the complaint are from the liberal United Church of Christ. They have called for ministers to oppose the ADF strategy by preaching the value of the separation of church and state on Sept. 21.

"The rightful place of religious leaders and communities of faith in American life is not in electoral politics," said the Rev. Eric Williams, one of the UCC ministers, according to The Associated Press.

Interestingly, the UCC denomination itself was investigated by the IRS last year for allowing Democratic presidential candidate Barack Obama speak at its convention in Hartford, Conn.

Williams and his group’s complaint is a counter measure to the Alliance Defense Fund initiative to recruit dozens of pastors across the country to endorse political candidates from their pulpit on Sept. 28.

ADF argues that clergy have a constitutional right under the first amendment to talk about politics in church, which directly challenges IRS rules for non-profit religious organizations.

The legal group expects its “Freedom in the Pulpit Sunday” plan will result in an IRS investigation in which ADF lawyers would then contest in federal court. Ultimately, the legal group hopes to take the case to the U.S. Supreme Court and persuade the judges to overturn the ban on political endorsements by tax-exempt organizations.

"For so long, there has been this cloud of intimidation over the church," ADF attorney Erik Stanley said. "It is the job of the pastors of America to debate the proper role of church in society. It's not for the government to mandate the role of church in society."

Stanley says some three dozen church leaders from more than 20 states have signed onto the plan to give a political sermon that includes names of candidates.

"The sermon will be an evaluation of conditions for office in light of scripture and doctrine. They will make a specific recommendation from the pulpit about how the congregation would vote," he said.

"They could oppose a candidate. They could oppose both candidates. They could endorse a candidate. They could focus on a federal, state or local election."

Stanley asserts that his group is not encouraging “any congregation to violate the law,” according to The Washington Post. But rather it is encouraging churches to “exercise their constitutional right in the face of an unconstitutional law.”

ADF was founded in 1994 for socially conservative Christians that include prominent evangelical leaders James C. Dobson of Focus on the Family and William R. Bright, founder of Campus Crusade for Christ.

The legal group is often involved in legal battles concerning religious symbols in public places, expression of faith in public schools, and same-sex “marriage” initiatives, among other religious freedom issues.

A survey released in August showed that most Americans believe churches and houses of worship should keep out of politics – the first time in more than a decade that the majority of Americans have held this view.