Writers across America are uniting against what the Pulitzer prize-winning authors Richard Ford and Junot Díaz called the "bone-heads in the South Carolina legislature" and "flat-out hate masquerading as concern for 'public sensibility'" after politicians looked to strip funding from two colleges as punishment for teaching books with gay-friendly themes.

The College of Charleston ran into trouble after assigning Alison Bechdel's acclaimed Fun Home to students; the graphic novel details Bechdel's coming out as a lesbian as a teenager, and her relationship with her closeted father. The University of South Carolina Upstate, meanwhile, was teaching a collection of radio stories about being gay, Out Loud: The Best of Rainbow Radio. Earlier this year, funding to the two schools of almost $70,000 (£40,000) was threatened because of the choices, described as pornographic and "forcing an agenda on teenagers" by their opponents; the issue has been under debate in the state senate this week, and authors have been coming together to stand up for LGBTQ rights.

"Only morons and mean children are afraid of free speech and fairness to all," said Gone Baby Gone author Dennis Lehane. Lehane is one of many writers to have taken a photo of themselves wearing an "I'm speaking out; support academic freedom; fight government censorship" T-shirt as part of the Writers Speaking Out campaign launched by Out Loud's publisher Hub City Press.

The Pulitzer-winning novelist Junot Díaz, author of The Brief Wondrous Life of Oscar Wao, joined the campaign "because censorship is the primal enemy of the artist and of a democratic society. Because our so-called leaders should be funding our university system, not censoring it. Because without LGBTQ artists what hope do any of us have? And because the just nation we deserve is not the one the politicians are trying to twist into being in South Carolina."

Emma Donoghue, author of Room, added that "censorship gives me the creeps", and that "university should blow your mind, or why bother going?" Ford, meanwhile, author of Independence Day, said that "the encouraging thing is that ignorant censorship of this sort doesn't work in the long run. People are who they are. The discouraging thing is that the bone-heads in the South Carolina legislature haven't figured that out. They will."

The prize-winning Ann Patchett, author of State of Wonder, also joined the campaign, telling Hub City that she "had a similar run-in with higher education in South Carolina a few years back and learned that academic freedom is a serious business", and that "we all need to stand up for what's right". In 2006, Patchett had been invited to lecture on her memoir Truth and Beauty – about her long friendship with the writer Lucy Grealy – at Clemson University, South Carolina, after it was assigned to students. A campaign against the book choice ensued – one protester wrote that the "the book talks in graphic terms about pornography, about fetish, about masturbation, about multiple sex partners … the explicit message that [Truth and Beauty] sends to students is that they are encouraged to find themselves sexually".

Patchett spoke at the university despite the protests, detailing her experience in an article for The Atlantic, and laying out the speech she made in which she asked students to "take a minute to think of all the other things you're going to need to be protected from … Faulkner is gone. Hemingway is gone. Toni Morrison, John Updike, and Philip Roth, our three greatest living American authors, are strictly off-limits to you. Their books contain so much sex and filthy language it's amazing I have mentioned their names on this stage."

Díaz, who also teaches at MIT, told the Free Times that students were desperate "for a better, more realistic, more complex, more human vision of their world than the ones that these legislators are trying to sell".

"My impression of this madness? That this was flat-out hate masquerading as concern for 'public sensibility'. That our politicians are always looking for excuses to defund our educational systems and this gave them the added opportunity to bash a vulnerable community as well – which for them was sort of a jerkoff's two-for-one," said Díaz.

The senate is preparing to vote on the issue of budget cuts to the colleges for assigning the gay-friendly texts, with debate to resume next week, said the campaigners. Democratic senator Brad Hutto has been a fierce supporter of the books, repeatedly asking his colleagues what they found offensive about the titles, according to an Associated Press report on the debate this week.

"Very few people recognise this book as pornography. Maybe in here. Maybe a bunch of old guys, but that's not how the world turns these days," said Hutto. "You're saying we're going to punish a university for daring to expose an adult – these are adults, this is not kindergarten – to a subject matter you find uncomfortable that they do not. This body has a hang-up on sexuality in general and homosexuality in particular."