New Jersey corrections officials say a best-selling book about mass incarceration and racial discrimination will now be available to inmates at all state correctional facilities.

The announcement came Monday after the state chapter of the American Civil Liberties Union questioned why at least two prisons had banned "The New Jim Crow" by Michelle Alexander. The group argued that the ban amounted to unconstitutional censorship of speech on issues of public concern, which is entitled to special protection under the First Amendment.

Corrections officials noted there was no department-wide ban on the book. They also say it's being used as a teaching tool in a state program in which inmates enroll in college-level courses while incarcerated.

Prisons and jails are allowed to ban reading materials based on some concerns, such as security.

But the ACLU argued that that justification did not apply in this case.