By Mary Wisniewski

CHICAGO (Reuters) - Political watchdog and secularist groups are asking the U.S. government to investigate whether Catholic bishops and a Christian evangelical group headed by preacher Billy Graham should lose tax breaks for telling followers how to vote in this year's election.

Under constitutional protections of free speech and separation of church and state, churches are free to speak on any issue. But they risk losing tax breaks worth $145 billion in the past decade if they violate Internal Revenue Service rules by promoting or opposing any particular candidate. Other non-profits also have special tax status.

Citizens for Responsibility and Ethics in Washington, a political watchdog group, in its complaint to the U.S. Internal Revenue Service, cited reports of individual bishops "abusing their positions to advocate against the election of President Barack Obama."

The group's executive director, Melanie Sloan, said some bishops went too far by saying a vote for Democrats would mean going to hell. "I don't think the Catholic bishops should be intimidating parishioners to advocate for any particular candidate," said Sloan.

The Wisconsin-based Freedom from Religion Foundation complained to the IRS about possible illegal political campaign intervention by Wisconsin Catholic bishops and the Charlotte, North Carolina-based Billy Graham Evangelistic Association.

IRS spokesman Dean Patterson declined to comment on the complaints or on whether there was any investigation. "Federal law prohibits the IRS from discussing specific taxpayers or situations," Patterson said.

The U.S. Conference of Catholic Bishops, through its spokeswoman Sister Mary Ann Walsh, said it would not comment on what a bishop says in his diocese.

The Billy Graham group said that its newspaper ads in publications like the Wall Street Journal and USA Today advocated votes for candidates who support "biblical values" but mentioned no candidate or party.

The ads, signed by Graham, asked voters to back candidates who support "the biblical definition of marriage between a man and woman" and who protect "the sanctity of life," an apparent reference to the group's opposition to abortion.

The conference of bishops waged a campaign this year against the Obama administration's health care requirement birth control be covered by health insurance.

Church doctrine is opposed to contraception as a means of birth control. Church leaders also spoke out against same-sex marriage but were on the losing side in four states where the issue was on the ballot.

THE POWER OF THE PULPIT

Nicholas Cafardi, a law professor at Duquesne University who worked for the Catholic diocese of Pittsburgh, said some bishops seemed particularly politically active in this election.

In Cafardi's opinion, the bishops' conference did not cross any tax-law lines but some individual bishops may have done so.

"The larger issue is that, irrespective of what the tax code says, churches should be sacred spaces, free of partisan politics," said Cafardi.

Among those whose political positions created controversy in this campaign season was Springfield, Illinois, Bishop Thomas Paprocki who warned his flock in a letter of "intrinsic evils" in the Democratic platform's support of abortion and same-sex marriage. A vote for someone who promotes such actions "places the eternal salvation of your own soul in serious jeopardy," he said. Continued...