The annual celebration of Pulpit Freedom Sunday on Oct. 7 encourages pastors to preach politics from the pulpit. The Internal Revenue Code exempts certain organizations including churches from taxation, but prohibits them as a condition of tax-exemption from “any political campaign on behalf of (or in opposition to) any candidate for public office.”

“Both the restriction and Pulpit Freedom Sunday raise important questions about the relationship between church and state, the role of religious argument in political discourse, and the significance of clergy in political debate,” says John Inazu, JD, professor of law at Washington University in St. Louis and expert on religion and the Constitution.

Inazu says that these issues are heightened even further during a presidential election season.

“This calls to mind a famous advertising campaign by Branch Ministries launched in national news media days before the 1992 presidential election,” he says.

Branch Ministries, a church in Binghamton, NY, took out full-page ads in USA Today and the Washington Post, encouraging citizens not to vote for then-candidate Bill Clinton. The IRS rescinded the church’s tax-exempt status, a move supported by federal court rulings.