This past Sunday, as churchgoers across the nation listened to sermons from their clergy, some may have heard a message they aren’t used to hearing while sitting in the pews: the endorsement of political candidates by their religious leaders.

The explicit mixing of politics and religion wasn’t a response to last week’s presidential debate. Instead, it was part of an organized effort by the Alliance Defending Freedom (ADF), a Christian-based legal organization known for leading efforts to restrict LGBT rights, that wants to repeal the government’s prohibition against charities, including churches, engaging in campaign politics. If the effort is successful, America’s campaign finance system would be turned on its head, with dark money flowing even more easily into politics.

Since 2008, ADF, along with conservative groups like the Family Research Council, have hosted Pulpit Freedom Sunday a few weeks before Election Day. The event encourages pastors across the country to talk electoral politics in church as part of a deliberate effort to draw scrutiny from the IRS so that ADF can launch a constitutional challenge to the law, known as the Johnson Amendment, that makes it illegal for non-profit charities to participate in elections.

ADF frames the issue by arguing “the IRS can use the Johnson Amendment to tell pastors what they can and cannot preach,” claiming that the “law aims to censor your sermon if the IRS labels it ‘political.’” But the IRS does not appear to have any interest in policing sermons. As the Wall Street Journal recently reported, the IRS didn’t open a single audit of a church during President Obama’s first term and initiated only three such audits in 2013 and 2014 combined. We don’t know if those audits even involved political activity.

Even one of ADF’s allies thinks repeal of the Johnson Amendment is a solution in search of a problem. “It’s a straw man,” Mat Staver of Liberty Counsel told the Wall Street Journal. “It’s not going to empower Christians because it’s not holding the community back.”

What it will do, however, is empower millionaires and billionaires to inject more money into the political system with even less accountability. Allowing charities to engage in politics would almost certainly lead to a new flood of dark money campaign spending by groups that don’t disclose their donors.

At the federal level, current tax and campaign finance law allows two kinds of outside groups to engage in political activity. So-called super PACs are political organizations that can spend as much money as they want on campaign activity, as long as they don’t coordinate their messages with candidates. Super PACs, however, must disclose their donors.

Several types of tax-exempt section 501(c) organizations – including “social welfare” groups, trade associations, chambers of commerce, and labor unions – also can engage in some political activity. These groups are not allowed to spend more than half of their budgets on politics, but they can keep their donors secret.

While both super PACs and section 501(c) organizations are largely exempt from paying taxes on their income or spending, donors may not deduct contributions to them from their taxes. Contributions to charities, on the other hand, are tax-deductible. Charities also do not need to disclose their donors.

All of this means that if ADF succeeds in getting the Johnson Amendment and related tax code provisions repealed, political donors and operatives would legally be able to shift many of their political activities to charities – and have a lot of incentives to do it.

Most of the dark money spending currently done by the non-charitable section 501(c) groups would almost certainly move to charities, as would at least some of the super PAC spending. The ability to deduct what would effectively be political contributions would be a massive incentive to contribute to charities that engage in politics, instead of to other section 501(c) entities.  Even better, donors could still keep their contributions secret. Deductibility of contributions and secrecy similarly would motivate donors to switch from super PACs – and from candidates and political parties – to political charities.

This shift would also make some dark money spending even darker. Most section 501(c) organizations must file Form 990 tax returns that provide some information about the group and its activities. Churches, however, are exempt from that reporting requirement. As a result, their political spending – the kind ADF particularly encourages – would be even more opaque.

Some constraints would still remain on charities. If a charity spent more than half of its budget on politics, it would become a political organization under federal tax law and would have to disclose its donors. But donors and their lawyers would have no trouble circumventing that limit.

Many charitable organizations are very large, and their charitable spending can easily counter-balance any campaign activity. The Salvation Army, for example, reported spending $3.5 billion in 2015. Also, many major political donors already control large foundations and charities they could easily use for political spending – Sheldon Adelson’s private foundation alone spent more than $100 million in 2015.

Indeed, ADF itself spent nearly $49 million in its 2014-15 fiscal year. So if it succeeds in its goal of repealing the prohibition on campaign activity by charities, ADF alone could spend tens of millions on politics.

Despite these serious and harmful consequences of repealing the prohibition on political activity by charities, the idea is gaining momentum beyond conservative Christian groups like ADF. The platform adopted at the Republican National Convention in 2016 for the first time called for repealing the provision, and in his speech accepting the Republican nomination for president, Donald Trump promised to “work hard to repeal that language.”

ADF last week also announced support for more targeted legislation that would allow charities to make political statements “in the ordinary course of the organization’s regular and customary activities” as long as the related expenditures are de minimis. But ADF’s support of this legislation does not necessarily mean the group and its allies have abandoned its goal of eliminating the Johnson Amendment in its entirety.

ADF’s press website promoting Pulpit Freedom Sunday starts by announcing that ADF “hopes to eventually go to court to have the Johnson Amendment struck down as unconstitutional.” Similarly, in a video promoting this year’s Pulpit Freedom Sunday, Family Research Council President Tony Perkins, who is working with ADF on the initiative, says the goal is to repeal the Johnson Amendment. He even urges viewers to tell their member of Congress “to repeal the part of the IRS code called the Johnson Amendment.”

Prayer may be an understandable response to this year’s election. That doesn’t mean that churches or other charities should be turned into vehicles to spend millions of dollars – given in secret and subsidized by a tax deduction – on politics.

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