Conservative leaders are coming together to push back against what they call renewed momentum on the left to force right-leaning organizations to disclose their donors.

The Conservative Action Project, a coalition of leaders from groups such as Heritage Action for America, Tea Party Patriots, and Club for Growth, released a memo urging fellow movement leaders to tell their members about the new “targeting” by liberals. They wrote:

The left is orchestrating an effort to harass and intimidate people who support conservative causes, a persecuted class. Part of their attack forces organizations like yours to report the names and addresses of your donors to the government, and then exposing those names and addresses on government websites for anyone to see.

The Jan. 15 memo, headlined “Stop the Momentum Forcing Donor Disclosure,” cited multiple cases of donors to conservative groups who were “outed” and later faced repercussions.

Brendan Eich, the former Mozilla CEO, for example, was forced out of the tech company after the Los Angeles Times revealed he had made a political donation in 2008 to the Proposition 8 ballot initiative in California preserving the definition of marriage as the union of one man and one woman.

The Conservative Action Project said the left’s new campaign, spearheaded by progressives fighting “anti-corruption” efforts such as RepresentUs, is an effort to “choke off [the] air supply of funding” from conservative organizations.

“Just as the right to pull the curtain closed behind us as we vote for our chosen candidates is sacrosanct, so too is our right to support charities and interest groups without the government standing over our shoulder and sharing the information with the wider world,” the coalition of leaders wrote.

In 2015,  they said, at least six states—Minnesota, Missouri, New Mexico, Pennsylvania, Tennessee, and Washington—either proposed or geared up to introduce bills to force donor disclosure.

The coalition said bills introduced in South Carolina and Texas, supposedly intended to eliminate corruption among state officials, ended up forcing private groups to report the names and addresses of their supporters to the government:

This is an affront to the deeply held values that are enshrined in the First Amendment. Every American has the right to support causes they believe in. To keep that right a reality, we must protect individual privacy.

The Conservative Action Project was founded by former Attorney General Edwin Meese, currently the Ronald Reagan distinguished fellow emeritus at The Heritage Foundation. The coalition includes leaders of more than 100 groups across the conservative movement.