Demanding apologies from polite dissenters, floating loss of citizenship as punishment for flag-burning: President-elect Donald Trump has given supporters of the First Amendment more than enough reason to squirm in the weeks since his victory.

PEN America, a literary and human rights organization, decided to respond by taking a public stand in defense of free expression. On Wednesday, the organization unveiled a pledge to defend the First Amendment that is cosponsored by Daily Kos, The Nation, People for the American Way and a number of progressive entities.

The pledge, which has been signed by Philip Roth, Salman Rushdie, Nicole Krauss and all living past U.S. poets laureate, calls out Trump’s pattern of threatening speech toward members of the media and disenfranchised groups since his presidential campaign commenced.

“Of specific concern were his threats and insults directed toward journalists, arbitrary limitations on media access and comments in support of potential legal reforms that would weaken First Amendment protections,” the statement reads. “The United States is recognized globally for having the broadest and most powerful protections for free speech in the world. But those protections are now under attack.”

During his campaign, Trump notably suggested that he’d “open up” libel laws if he were to be elected, enabling him to sue publications that published unflattering stories about him. And while many news outlets dismissed the proposition as unlikely, it seems possible. He also notoriously blackballed media outlets that covered him critically, refusing them credentials for his campaign events.

In response to these actions, PEN America and its partners are soliciting reader signatures as well, asking the public to “[d]efend the vital role and the rights of a free press in a democracy,” “reject the bigotry and hate that are creating a widespread and alarming chilling effect on freedom of expression for people of color, Muslims, Jews, the disabled, immigrants, LGBTQ, and women,” and otherwise show support for freedom of speech, assembly, religion and expression.

Read the full pledge here.