Black Protestants are much more likely than Catholics, white evangelical Protestants and white mainline Protestants to hear their clergy directly speak out supporting or opposing a presidential candidate, a new report by the Pew Research Center has found.

In a survey of 4,602 adults, researchers found that three in 10 black Protestant churchgoers have heard their clergy directly speak in support of or against a presidential candidate.

This is a much higher percentage than other congregations, for which roughly one in 10 or fewer churchgoers say their clergy have publicly supported or opposed a presidential candidate.

The question of whether and how clergy can speak on religion can be complex and misunderstood. While it is not against federal law for clergy to speak out directly for or against particular candidates, churches, as nonprofit institutions, risk losing their tax-exempt status in doing so, said John Green, a political scientist at the University of Akron and a senior fellow with the Pew Forum on Religion and Public Life.  At issue is the role and purpose of tax deductions for non-profits.

“If a number of clergy got up and endorsed Hillary Clinton or Donald Trump … [and] if the IRS pursued that, it might revoke their tax-exempt status,” Green explained.

Outside the pulpit, clergy can certainly express their opinions like any other American, Green said. It is also recognized that nonprofit organizations can take positions on issues such as war, poverty and abortion. The potential problem arises, Green said, “when it’s a pretty clear endorsement of a candidate.”

The survey asked if, in the past few months, “clergy at your place of worship [has] spoken out” in support of or against a particular candidate. The question did not explicitly ask whether clergy had spoken from the pulpit, or in some other context outside the church, Pew said.

Jessica Martinez, a senior research at Pew and the lead author of the report, said that while it’s hard to hypothesize from the survey data about why black Protestants are more likely to hear their clergy openly supporting or opposing a particular candidate, one thing to keep in mind, she said, is the fact that the black church in America has historically played a particularly strong institutional role.

Green said there are two key reasons black Protestants have the highest degree of tolerance for political discussion in this particular context of the survey.

The first is historical. The black church played a central role in the civil rights movement, Green explained, and throughout history it has played a much more expansive role than evangelical or Catholic congregations.

The second reason, Green said, is the relative ethnic, racial and political homogeneity of black congregations.

“Black congregations are more homogeneous than white congregations or mixed-race congregations,” he said, and hence the views on political and social issues tend to be much more similar in black congregations.

The Roman Catholic Church, for example,  is larger, ethnically more diverse and also has a greater diversity in political perspectives, Green said.

In many congregations, there is also pushback from churchgoers on what the clergy might say. “The more heterogeneous the congregation, the more likely the pushback,” Green said. But because of the history of segregation, black churches tend to be overwhelmingly black.

Black Protestant clergy are also much more likely to speak out in support of Clinton and against Trump, the Pew researchers found.

Among black Protestants, 28 and 20 percent said their clergy have spoken out in support of Clinton and against Trump respectively, the survey results showed.

This compares with less than 1 percent of white mainline Protestants who said their clergy had spoken in support of Clinton, and one percent who said their clergy had spoken in support of Trump.

Pew hasn’t asked the question before, Martinez said, so it’s not possible to know if such talk by clergy is growing, shrinking or neither.

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