BILLINGS, Mont. — The American Civil Liberties Union says a yearlong investigation of Montana's corrections system revealed widespread mistreatment of mentally ill prisoners.
The group says mentally ill inmates are routinely subjected to long periods of solitary confinement, denied needed medicines and punished for behavior caused by their illness.
It says there are only 12 mental health beds for more than 275 mentally ill prisoners.
The findings were detailed in a letter to state officials released Friday in which the ACLU warned it will sue the state if changes aren't made.
Department of Corrections Director Mike Batista says his agency has taken steps to improve mental health services and will analyze the allegations.
In 2012, state officials settled an ACLU lawsuit over a juvenile inmate in solitary confinement and agreed to change some procedures.