For the past two years, free speech organizations have tracked a spike in book bans across the country, fueled by a growing and organized movement to remove books on certain subjects from school districts and libraries.

PEN America has counted more than 4,000 instances of book removals since it began tracking bans in July 2021. A recent report from the American Library Association found that efforts to ban books nearly doubled in 2022 over the previous year, and reached the highest levels that the organization has seen since it began gathering data on book bans more than 20 years ago. Most of the targeted books are titles that feature L.G.B.T.Q. themes and characters, or works that address race and racism, both organizations found.

Opponents of book removals have expressed alarm not only over the sharp rise in bans, but in the methods that are being used to challenge books. Whereas in the past, book challenges often came from concerned parents, many are now coming from the organized efforts of conservative groups like Moms for Liberty and Utah Parents United, or from statewide legislation that has made it easier to get titles removed.

In recent months, a counter movement by those who oppose book removals has started to take shape. In Llano, Texas, a federal judge ordered the county to restore 17 banned books to its library, after a group of residents sued the county and library officials, arguing that the book removals were unconstitutional and violated citizens’ First Amendment rights.

In Illinois, the legislature has passed legislation that would withhold grant funding from libraries that remove books, or refuse to adopt a policy against book banning.

Last week, PEN America and the publisher Penguin Random House, along with a group of authors and parents, filed a lawsuit against a Florida school board and district over book removals.

“Children in a democracy must not be taught that books are dangerous,” Suzanne Nossel, chief executive of PEN America, said in a statement about the suit. “The freedom to read is guaranteed by the Constitution.”