The American Civil Liberties Union asked the Wyoming Department of Corrections to revise its policy on inmates wearing kippahs.

On behalf of Clarence Fisher, an Orthodox Jewish inmate, the ACLU and the ACLU of Wyoming sent a letter on Jan. 9 to the Department of Corrections saying that its refusal to allow Fisher to wear his kippah at all times violates his religious freedom.

The Corrections Department allows a prisoner to wear a kippah only in his own cell or during religious services, according to the ACLU, which said the department cited non-specific “security concerns” for refusing to accede to Fisher’s request to wear a kippah at all times in accordance with his religious beliefs.

The ACLU noted that prisoners can wear baseball caps and hats purchased at the prison commissary, and that Jewish inmates in federal prisons are permitted to wear a kippah at all times.