Earlier this month, we wrote about a successful campaign by the ACLU of New Jersey to remove Michelle Alexander’s book The New Jim Crow from the list of banned books in at least two New Jersey prisons.

Since then, similar efforts have spread to North Carolina, where state officials lifted the ban on Alexander’s book within a day of receiving a letter of complaint from Chris Brook, legal director for the North Carolina ACLU. In an interview with NPR affiliate WUNC’s The State of Things, Brook said the swift response from the Department of Public Safety (while appreciated!) suggests that there really was never a good reason for the book to be on the list in the first place.

It’s a violation of inmates’ constitutional rights, for one thing, but the ban also highlighted a “real perversity in preventing prisoners who are very familiar with the racial disparities in our prison system here in North Carolina from accessing a book that talks about mass incarceration and talks about racial injustices in our criminal justice system.”

Both Brooks and Michele Luecking-Sunman, an attorney who works with North Carolina Prisoner Legal Services, called for a broader look at how the rules about what inmates can and cannot read are written, and how they’re being applied across the state. As it is, the system is dubiously subjective—it begins in the mailroom, where a staffer can flag any material he or she finds questionable—and it’s plainly unclear why publications like The American Heritage Dictionary and a particular issue of the O, The Oprah Magazine are still restricted.

Listen to the complete interview here, and check out Books Through Bars to find out how you can help.