But four years later, after The Boston Globe reported on the guards' rough treatment of Messier on the night he died, Attorney General Martha Coakley appointed a special prosecutor to investigate.

The trial, scheduled to unfold in Plymouth Superior Court, once seemed highly unlikely even though the medical examiner ruled that the guards caused Messier's death. Plymouth District Attorney Timothy J. Cruz in 2010 determined there was insufficient evidence to pursue criminal charges, and none of the guards was charged or even disciplined.

Eight years after the tragic death of a 23-year-old patient with schizophrenia at Bridgewater State Hospital, three prison guards are slated to stand trial Tuesday on charges they killed Joshua K. Messier while forcefully strapping him to a bed in a brutal scene captured on prison video.


Now guards Derek Howard, John C. Raposo, and George A. Billadeau face charges of involunt-ary manslaughter and criminal civil rights violations.

"We've waited a long time for this day, and we're happy that some of the guards who were in Joshua's cell the night he was killed will finally have to account for his death," said Lisa Brown, Messier's mother, who had visited her son only hours before learning he was dead. "We're hoping for a verdict that will send a message to people everywhere that mental health patients like Joshua can never be treated this way again."

But Kenneth H. Anderson, Howard's attorney, said that the extraordinary legal actions undertaken to prosecute the guards were politically motivated — the attorney general named the special prosecutor during her unsuccessful campaign for governor — and that each of the guards maintains his innocence.

"They've been treated unfairly by the system throughout the entire process, and we're looking forward to a day in court to air things out and vindicate them," Anderson said. "This has been highly political from the outset."


R. Michael Cassidy, a Boston College Law School professor and former head of the attorney general's criminal bureau, agreed that it's unusual for a special prosecutor to pursue criminal charges after the local district attorney has declined to do so. But in the Messier case, he said, "there was high sentiment that a thorough investigation wasn't undertaken in the first place."

Messier's death has already triggered widespread reform at Bridgewater State Hospital, which, despite its name, is a medium-security prison.

The Intensive Treatment Unit, where Messier was killed and where other patients were restrained or held in solitary confinement for prolonged periods, has been closed. And all the guards at Bridgewater have been reassigned and replaced with a private security force trained in handling men with a serious mental illness who may become violent.

In addition, Messier's family settled a lawsuit against the state for $3 million, far more than the $100,000 cap that usually applies to judgments involving the actions of state employees.

But until now, no one has been held criminally responsible for the death of Messier, who had been ordered by a judge to undergo a psychiatric evaluation at Bridgewater after he allegedly assaulted staff in the psychiatric unit at Harrington Memorial Hospital, in Southbridge. He had been held at Bridgewater for little more than a month when he was killed.

Messier's mother had left the hospital at about 9 p.m. on May 4, 2009, when he headed toward what would be a fatal confrontation with prison guards. Messier, whose illness caused him to hear voices and hallucinate, walked into a break room used by guards, where he scuffled with two of them in an altercation that spilled out into a hallway and was joined by more than a half-dozen other guards.


In a crucial sequence captured on grainy prison video, Messier was then escorted into the Intensive Treatment Unit and taken to a cell, where seven guards began placing him in what is called "four-point restraints," seating him on a bed with his legs extended in front of him, while his hands remained cuffed behind his back.

Then Howard and Raposo pushed down hard on Messier's back, bending him over until his chest appeared to nearly touch his knees, a procedure sometimes referred to as "suitcasing" that is banned in Massachusetts prisons because it can cause suffocation, especially with patients like Messier, who was overweight due to medications he was taking.

After the guards secured Messier's ankles to the bed restraints, the video shows, they unfolded his body, lying him on his back, and he never moved or said another word.

Yet the guards continued the four-point restraints procedure without checking Messier's vital signs, casually placing his wrists in the bed restraints and stripping off his clothes with a pair of shears. At one point, as they lifted Messier's torso to take his clothes out from under him, Messier's head flopped back at a 90-degree angle, his neck completely slack, but the guards appeared to be unconcerned.


Eventually — more than seven minutes after the guards unfolded his body — a nurse checked for Messier's pulse and sounded an emergency alarm, but Messier was declared dead after being rushed to Brockton Hospital.

District Attorney Cruz declined to pursue criminal charges, saying in a statement to the Globe that the medical examiner, Mindy J. Hull, was unable to identify a specific cause of death and told investigators from his office that Messier was responsible for his own demise because he started a fight with the guards.

Hull never formally changed her finding that Messier's death was a homicide. During a judicial inquest called for by special prosecutor Martin F. Murphy, she testified she was "a little bit angry" that Cruz, in his statement, made it seem as though she blamed Messier for causing his own death.

Cruz declined to comment for this story.

He was not the only official who faced questions over his handling of the Messier case. An assistant deputy commissioner at the Department of Correction overruled an internal affairs report that found Howard and Raposo had violated the policy that prohibits guards from putting pressure on a restrained inmate's back, even if the inmate is resisting. As a result, the guards were not disciplined for their treatment of Messier.

But after the Globe published its findings in 2014, then-Governor Deval Patrick announced sweeping disciplinary measures against all three guards and three high-ranking department officials, including Commissioner Luis S. Spencer. Patrick later forced Spencer to resign, officials said, because of a variety of problems at Bridgewater.


Before Patrick acted, Messier's parents in 2012 had filed a civil lawsuit against the guards and the Department of Correction, and Attorney General Coakley's office was defending the guards. During pretrial testimony, the guards said they had little or no training in dealing with men afflicted by a serious mental illness and little or no training in the use of four-point restraints.

After the lawsuit settled, Coakley's office stopped representing the guards and appointed special prosecutor Murphy, which led to the criminal charges.

Now, attorneys for the guards say all charges against them should be dropped because they have been defended and prosecuted by the same agency — the attorney general's office — and because evidence collected during the civil suit is being used against them in the criminal case.

In a motion to dismiss the charges, attorney Anderson said, "At no time did [the guards] expect to be double-crossed by the Attorney General's office or have the information they freely shared under the guise of attorney-client privilege used as part of a decision to appoint a special prosecutor or to be presented against them at an inquest." Because the case has been delayed for a long time, all parties agreed to consider the motion to dismiss after the trial.

Cassidy, the Boston College Law School professor, said it is unlikely that the actions of the guards would have been seriously scrutinized for possible criminal violations were it not for the appointment of a special prosecutor, because district attorneys rarely seek criminal charges against law enforcement officers.

"These cases are very rare," Cassidy said. "That's why we have a special prosecutor here."

Michael Rezendes can be reached at michael.rezendes@globe.com. Follow him on Twitter @mikerezendes.