DETROIT — A judge dismissed involuntary manslaughter charges Monday against six Michigan Department of Corrections employees in the death of a prisoner who lost more than 50 pounds in 15 days and died while being restrained in 2019.

District Judge Charles Nebel said two former prison officials and four registered nurses failed to provide or ensure the required level of care to Jonathan Lancaster, who was 38 when he died in solitary confinement at Alger Correctional Facility in Munising, Michigan.

But there's not enough evidence to send any of the defendants to trial because none of their failures directly caused Lancaster's death, Nebel ruled. The judge said he relied on expert medical testimony that Lancaster was already "doomed to die from dehydration" by the time he was moved to an observation cell and died three days later.

Lancaster's sister, Danielle Dunn, who has pushed for answers and accountability in the case, said in an email she is "beyond devastated" by the ruling.

“This is not the end for us,” Dunn told The Associated Press. “We will fight for an appeal and continue to advocate for other families like ours as well as current incarcerated citizens.”

Lancaster's death also highlights inadequate conditions in prisons across the country. Advocates for prison reform have noted the growing number of incarcerated people in U.S. prisons, where many have been criticized for negligence, poor infrastructure, and corruption.

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What happened to Jonathan Lancaster?

Lancaster was in prison for robbery and gun crimes in the Detroit area. His family said he had a history of mental illness and showed symptoms while at the Alger Correctional Facility, including paranoia, anxiety, loss of appetite and insomnia.

Lancaster had stopped eating and drinking, causing his sodium levels to get so elevated that he could no longer communicate or respond to officers' directions, Nebel said.

By the time of his death, Lancaster had missed nine consecutive meals, according to Nebel. The judge pointed to holes in Michigan Department of Corrections policies, which at the time may have contributed to a "perfect storm" and Lancaster's death.

Nurses had performed the required daily checks of Lancaster's vital signs and were shown to be within normal ranges, Nebel said. But mandatory daily weight checks were not conducted, according to Nebel, because weight checks were not typically performed on weekends.

Lancaster had also been placed in restraints while in confinement and was found lying in his own feces and urine. He lost more than 50 pounds in 15 days, according to evidence in the case.

Michigan judge says incident wasn't regarded as a crisis

Some testimony had argued that weight checks would not have made a difference in saving Lancaster's life, but Nebel said the checks should have been done, regardless.

Nebel added that if he had been seen in the condition he was in on a park bench or almost anywhere else in society, medical intervention would have happened as he was "in an absolute crisis situation." But under the existing Michigan Department of Corrections policies and procedures, no one was viewing the situation as a crisis, Nebel said.

Involuntary manslaughter charges, which is a 15-year felony, were dismissed against former Acting Warden Scott Sprader; former Assistant Deputy Warden Benny Mercier; and former nurses Paul Zelenak, Nathan Moser, Barbara Bedient and John Crane.

The six people were fired and several more were disciplined after Lancaster’s death. The state corrections department had referred the case to state police for investigation.

Separately, two corrections officers, Jason Denman and Shawn Brinkman, have been bound over to circuit court on charges of misconduct in office.

In announcing the charges in June, Michigan Attorney General Dana Nessel said Lancaster's death was "a preventable tragedy that played out over days and under the defendants’ supervision." Nessel's office is reviewing the ruling and "evaluating its next steps," spokesperson Danny Wimmer said.

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US prisons face criticism over conditions

Today, nearly 2 million people are incarcerated in the United States, according to the Prison Policy Initiative's 2023 report on mass incarceration.

Federal and state investigations have revealed corruption, abuse and escalating violence in U.S. prisons. Advocates have said these conditions violate the constitutional rights of inmates, where people face physical harm, sexual assault, poor living conditions and are denied access to proper medical care.

In 2022, a Senate panel revealed widespread corruption and abuse at the federal penitentiary in Atlanta, where staffers routinely helped traffic weapons and drugs.

"These were stunning failures of federal prison administration that likely contributed to the loss of life," Sen. Jon Ossoff, chairman of the Senate Investigations subcommittee, said during a congressional hearing in July 2022. "Conditions for inmates were abusive and inhumane, and should concern all of us who believe in our country’s constitutional traditions."

A USA TODAY analysis of media reports and information from state corrections department, found that at least 44 states lack universal air conditioning in their prisons. And as climate change brings more heat waves with scorching temperatures, experts have warned conditions in facilities could become deadly.

And more than half of inmates have a mental illness, which is often left untreated in prisons, according to the Equal Justice Initiative. The non-profit legal organization said solitary confinement can aggravate mental health problems.

"Studies show that people held in long-term solitary confinement suffer from anxiety, paranoia, perceptual disturbances, and deep depression," according to the Equal Justice Initiative. "Nationwide, suicides among people held in isolation account for almost 50% of all prison suicides, even though less than 8% of the prison population is in isolation."

Contributing: Kevin Johnson, USA TODAY; The Associated Press

Contact Paul Egan: 517-372-8660 or [email protected]. Follow him on X, formerly known as Twitter, @paulegan4.