A book arguing mass incarceration subjugates black population to permanent second-class status is banned in some of New Jersey's own prisons.

The American Civil Liberties Union discovered the ban on "The New Jim Crow" via a public records request, and Monday called on the state Department of Corrections to "immediately end their unconstitutional censorship and restore access to the book."

It said both New Jersey State Prison and Southern State Correctional Facility ban the book as official policy.

According to the ACLU, black people are imprisoned at more than 12 times the rate of white people in New Jersey, although black people make up less than 15 percent of the state population — and that disparity "makes the ban on a book exploring the injustices and racial inequities of mass incarceration especially shameful. "

“For the state burdened with this systemic injustice to prohibit prisoners from reading a book about race and mass incarceration is ironic, misguided, and harmful. It’s also unconstitutional,” ACLU-NJ Staff Attorney Tess Borden said in a statement released by the group on Monday. “New Jersey needs to eradicate its worst-in-the-nation racial disparities, not paper them over with a banned book list, hoping that people trapped in an unfair system will remain blind to its injustices.”

It said the ban "amounts to censorship of speech on issues of public concern" — noting prisons and jails are allowed to ban reading material based on security and certain practical concerns, but not based on philosophies.

The New Jersey Administrative Code does, however, allow prisons to ban material that "incites violence based upon race, religion, creed or nationality and (if) a reasonable inference can be drawn, based upon the experience and professional expertise of correctional administrators, that it may result in the outbreak of violence within the facility"

And it can ban material officials determine "is detrimental to the secure and orderly operation of the correctional facility."

"It is one thing to prevent incarcerated people from reading how-to manuals about lock picking; it is something altogether different to deny people access to a book that offers a timely and original framework for understanding mass incarceration," the ACLU said in its letter to the DOC, published by NJ.com Monday.

The ACLU also said Texas, "which has deservedly received criticism for its 10,000-title list of banned reading materials," allows "The New Jim Crow." But te book's official Twitter account Monday said New Jersey was just one of several states to ban "The New Jim Crow."

It's far form the only material banned by New Jersey prisons. According to documentation received by the ACLU and published by the Intercept, some New Jersey prisons ban magazines including Hunter's Magazine and Outdoor Life.  Men's magazines such as Stuff and Maxim frequently appear on the banned lists, as do manga comics, tattoo publications, pornographic magazines and books on drugs or other substances.

The Southern State Correctional Facility, one of the two to ban "The New Jim Crow, also bans books including DMX's autobiography, "Lincoln" and "How to Keep Your Kids Away from Gangs."  The ancient Chinese military treatise "The Art of War" is banned from the facility, as is Machiavelli's "The Prince."

A spokesperson for the state Department of Corrections said her office was working on putting together a response to inquiries about the ACLU's concerns and expected to be able to address the matter later Monday.

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