The national movement to censor books in both school and public libraries has escalated dramatically — and it’s a dire warning for the future of democracy, according to Boston Public Library president David Leonard.

“[Libraries] should have all viewpoints and all information represented to help people with their information needs or reading,” Leonard told Boston Public Radio on Friday.

“I think it’s incredibly important to acknowledge that public libraries have a special responsibility for voices that are otherwise not uplifted in society, whether it’s the kid who’s coming out, whether it’s someone who’s trying to understand the history of this country and slavery from multiple perspectives,” he went on. “Having all of those viewpoints in the library is essential to democracy.”

A PEN America report found more than 2,500 instances of individual books being banned in classrooms and libraries from summer 2021 to summer 2022, many of which were linked to political pressure from lawmakers.

The books challenged most frequently deal with sexuality, gender identity, and race and racism. And while many libraries have avenues for people to challenge books in their collections, Leonard argues for careful consideration when it comes to restricting books.

“Let’s let the librarians do the job about what are the right things to have in the collection,” Leonard said. “Let them do their jobs and then people can choose what they want, or what they need or what’s appropriate for their family and their belief systems.”