Dozens of Jewish nonprofits, charitable organizations and religious institutions are urging Congress to oppose efforts to weaken or repeal a law that prohibits tax-exempt nonprofits from supporting or opposing candidates for public office.

letter signed by 55 Jewish groups was sent Wednesday to the chairman and ranking member of the U.S. House of Representatives Ways and Means Committee, which is scheduled to discuss in the coming days comprehensive tax reform. The letter urges the committee to oppose the inclusion of any measures that would undermine the Johnson Amendment, the existing law that prohibits tax-exempt nonprofits from endorsing or opposing candidates.

“Charitable nonprofits and houses of worship can only be successful if we maintain public trust in our integrity and commitment to mission,” the letter reads. “Politicizing them for the benefit of politicians and partisan donors would destroy that trust. Every charitable dollar spent on partisan campaign politics is one less dollar spent on the public good.”

The letter also said: “Under current law, charitable nonprofits enjoy broad latitude to speak on important public matters, advocate on policy issues, encourage people to vote, and even host candidate debates and forums. Repealing or weakening the Johnson Amendment risks dividing charities and houses of worship along partisan lines. At a time when our political climate is already so polarized, we stand firmly against any measure that would bring politics into our organizations and reduce our effectiveness.”

Groups representing all streams of Judaism except the Orthodox community signed the letter, as did Jewish community relations councils and the Jewish federations of several cities. The Jewish Federations of North America and the Jewish Council for Public Affairs also signed the letter, as did the American Jewish Committee, Anti-Defamation League and B’nai B’rith International.