One of the biggest applause lines of the Republican convention was Donald Trump’s call to repeal the so-called Johnson Amendment, which, among other things, conditions churches’ tax-exempt status on ministers refraining from political speech at their pulpits. Critics such as Trump argue that ministers have First Amendment speech rights, which they say the government is infringing by restricting religious organizations in this manner. Or as Trump put it on Thursday night, addressing religious voters in general and evangelical ones in particular:

You have much to contribute to our politics, yet our laws prevent you from speaking your minds from your own pulpits.

An amendment, pushed by Lyndon Johnson many years ago, threatens religious institutions with a loss of their tax-exempt status if they openly advocate their political views. I am going to work very hard to repeal that language and protect free speech for all Americans.

In truth, it’s a lot more complicated than that. With Trump, it always is. Because on closer inspection, it’s clear that the Johnson Amendment, made law in 1954, serves an important function: preventing the government from subsidizing political speech. And repealing the law could lead to more entanglement of church and state—not less.

First, it’s important to remember that religious leaders are free to engage in political speech. Indeed, many religious leaders, on both sides of the aisle, have endorsed the candidates this election cycle, as they have in the past. That was certainly true of the minister who kicked off the Republican convention by declaring Hillary Clinton to be the enemy. We have always had ministers in Congress, and serious efforts are underway to recruit more.

So what is the problem with political speech from the pulpit? The answer lies in the nature of the tax subsidy that churches and other tax-exempt organizations receive and the government’s decision not to subsidize political speech. Subject to the various contribution limits, people can donate all they want to candidates, political parties, and political action committees, but they cannot deduct those amounts from their tax bills. Allowing deductions would mean that taxpayers would be subsidizing—through the tax code—the political activities of others. Allowing churches (and other tax-exempt organizations) to engage in political activities would create a backdoor way to subsidize political speech. And because it would happen through tax deductions for the donors, wealthier taxpayers in higher brackets would get the biggest subsidies.

Churches, charities, and educational institutions are tax-exempt under section 501(c)(3) of the U.S. Internal Revenue Code, which not only exempts their income from taxation, but it also allows them to receive tax-deductible donations. Organizations that are tax-exempt under other provisions, including politically active organizations, may not receive tax-deductible donations. It is not difficult to imagine what would happen if we suddenly allowed churches to engage in political activity and retain their current tax-exempt status. Political donors in search of a deduction would find willing churches and use them to fund political activity.

Indeed, we’ve already seen something like this in the case of 501(c)(4) organizations. Traditional political organizations must disclose their donors. But social welfare organizations, which are tax-exempt under section 501(c)(4) of the Internal Revenue Code, need not. Such organizations are supposed to be “devoted exclusively to charitable, educational, or recreational purposes,” but the Internal Revenue Service has interpreted “exclusively” to permit a significant amount of political activity. Not surprisingly, donors have flocked to these organizations to avoid having to disclose their activities. IRS efforts to police these organizations to ensure they do not go over the line are politically fraught, leading to significant abuse by taxpayers and charges that the IRS is biased and engaged in political witch hunts. Indeed, the IRS’s ham-fisted efforts to police organizations seeking 501(c)(4) status have led to the resignation of Lois Lerner, countless congressional hearings, and an unwarranted and clearly partisan effort to impeach the current IRS commissioner.

On the entanglement front, critics of the Johnson Amendment are not entirely wrong when they worry about the government monitoring and regulating religious speech, though in practice the rule is seldom enforced. However, that concern can be easily remedied. To avoid oversight, all churches need to do is give up their right to receive tax-deductible donations. A half-measure, denying deductions only for donations used for political purposes, would simply require greater IRS oversight and entanglement and open the door to abuse and fraud, as John Oliver has so trenchantly explored in other contexts.

Few would suggest that religious views have no place in the public square or that religious views should not inform one’s political decisions. Indeed, the problem isn’t that churches want to become politically involved. To a large extent, they already are. It’s that they want to make use of government subsidies to do so. The notion that those who receive government subsidies should be subject to reasonable restrictions is not new. Indeed, many of those clamoring for the repeal of the Johnson Amendment likely support efforts to drug-test welfare recipients. But unlike the parsonage exemption, which allows ministers to get tax-free housing and benefits only religious organizations, this is a broadly applicable law that happens to also apply to churches, much like section 501(c)(3), under which they receive their exemptions in the first place.

Unless and until we decide to subsidize all political speech (via, say, campaign finance reform), we need to think long and hard about allowing churches and other 501(c)(3) organizations to become more politically active. Making it easier for churches to tie themselves to political parties and politicians could lead to even greater entanglement between church and government than now exists, and it could ultimately do serious harm to them both.

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