The Washington, D.C.-based Citizens for Responsibility and Ethics in Washington (CREW) has asked the IRS to investigate the U.S. Conference of Catholic Bishops, alleging that numerous bishops had violated federal tax law by engaging in partisan advocacy.

"As a 501(c)(3) organization, the Conference is barred from any and all political activity, including endorsing candidates for public office. Yet based on the numerous statements and letters made by the bishops as well as the timing of the statements coming so soon before the election, there is ample evidence that the Catholic Bishops are engaged in a concerted and organized effort to make a last ditch effort to persuade members of the Catholic church to vote against President Barack Obama," CREW Executive Director Melanie Sloan told the IRS on Friday.

The complaint noted that Bishop Daniel R. Jenky of the Diocese of Peoria has urged his parishioners to vote against President Barack Obama. In a letter sent to area Catholics, Jenky said there was nothing more threatening to religious liberty than President Barack Obama and Democrats in the Senate because they supported a new Health & Human Services Department rule that requires most employers to provide free birth control coverage in their health insurance plans. Earlier this year, Jenky compared Obama to Adolf Hitler and Josef Stalin.

In addition, Bishop Nicholas DiMarzio of the Diocese of Brooklyn recently authored a letter in which he said it was "inconceivable to me how Catholics could support" Obama's policies. The letter blasts Obama for speaking about "women’s rights in the context of abortion and contraception" while allegedly ignoring Catholics' objections to those issues.

And the list goes on: Wisconsin Bishop David Ricken has suggested Democrats support "intrinsic evils," Alaska Bishop Edward J. Burns has compared Vice President Joe Biden's support of abortion rights to slavery, and Virginia Bishop Paul S. Loverde has indicated that Catholics could help the Church by voting against Obama.

The Internal Revenue Code prohibits 501(c)(3) organizations, including churches and charities, from intervening or participating in political campaigns. Citing court rulings, CREW noted that a church or non-profit organization could endanger its tax-exempt status by using "publications and broadcasts to attack some candidates and support others," even it if hadn't officially endorsed a candidate.

However, a spokesperson for the IRS recently said the agency had halted audits of churches engaging in political activity in the last three years. A federal court ordered the IRS to clarify who could authorize the audit of churches in 2009, but the agency has not yet adopted new regulations.