A Wisconsin organization that represents atheists and agnostics is suing the head of the Internal Revenue Service, asserting that the agency is failing to enforce tax laws on political activity by churches and faith groups, the Associated Press reports. The federal case filed Wednesday by the Freedom from Religion Foundation seeks a court order that IRS Commissioner Doug Shulman initiate enforcement of statutes barring overt electioneering by tax-exempt groups, including religious entities.

The complaint cites newspaper ads taken out by the Billy Graham Evangelistic Association urging voters to back candidates who support biblical values; an order by the bishop of Peoria, Ill., that priests in the diocese publicly urge Catholics to vote for abortion foes; and Pulpit Freedom Sunday, an organized national event in which some 1,500 pastors endorsed candidates from the pulpit. None of the events triggered IRS action.

An IRS spokesman in Wisconsin declined to comment on the suit. The agency has not been investigating complaints of partisan activity by religious groups since 2009, when it was ordered by a federal court to clarify which high-ranking official could authorize audits over nonprofit groups’ politicking.