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MIAMI (CBSMiami/AP) — A criminal investigation is underway in the death of a Florida inmate found in a scalding shower, U.S. Justice Department officials confirmed Wednesday.

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There may also be a broader civil rights probe into allegations of abuse of mentally ill inmates.

Existence of the criminal investigation into the 2012 death of Darren Rainey, 50, was confirmed in a recent Justice Department letter to the American Civil Liberties Union of Florida, which last year requested the probe. Rainey, who suffered from schizophrenia, died after he was locked in the shower at Dade Correctional Institute as punishment for refusing to clean up feces in his cell.

The letter also says the Justice Department’s Civil Rights Division is considering a “pattern or practice” probe into allegations of mistreatment of mentally ill inmates across Florida prisons. Such investigations can lead to court-enforced changes in the system and lengthy federal oversight.

“The investigation of state and local officials who abuse their positions of authority always has been, and remains, a high priority of this administration,” said Alexa Campbell, intergovernmental liaison at the Justice Department, in the March 17 letter.

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Florida’s prison system has come under fire for suspicious inmate deaths, poor conditions and alleged cover-ups of wrongdoing. Gov. Rick Scott earlier this month ordered a series of changes including beefed-up review of prison operations, safety and use of force incidents, among other things.

Howard Simon, executive director of the ACLU of Florida, said Wednesday the Justice Department investigation wouldn’t be necessary if state prison officials had been doing their jobs.

“There must be a change in the culture in Florida prisons, but that is not going to happen until officials are routinely held accountable for the brutality that too often characterizes our state prison system,” Simon said.

Florida’s prison system is one of the nation’s largest, with more than 100,000 inmates. The federal investigation into Rainey’s death was first reported by The Miami Herald.

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