ANNAPOLIS, Md. (AP) — Maryland is limiting the access prison inmates have to books, saying it’s necessary to keep drugs from entering state prisons.

The Washington Post obtained a memo announcing the statewide policy issued April 25.

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The police says Inmates may buy only 10 books every three months from vetted vendors with print catalogs, and cannot receive books from online retailers, relatives or friends. Federal prisons tried this before, but ended the experiment after it became harder and more expensive for inmates to read.

Corrections department official J. Michael Zeigler says 3,422 Suboxone strips were discovered last fiscal year. He didn’t say how many had been concealed in books.

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ACLU Maryland attorney Sonia Kumar called the policy “irrational” and says the civil liberties organization is evaluating legal options.

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