The announcement on Monday of charges against Major Evans and two others - Lt. Kashka Meadors and James Ramsey-Guy, a correctional officer - came more than nine months after that inquest, a relatively rare court proceeding in which jurors review evidence relating to a death and decide whether to recommend charges.
Police detectives asked Evans in a questionnaire during their investigation whether there was any documentation showing whether the water was turned off the whole time or intermittently.
Shortly after Thomas' death, Evans sought out subordinate officer, Capt. George Gold, and requested he watch surveillance video to determine whether the officers did in fact turn off the inmate's water.
Ms Evans could face more than four years in prison if she is convicted of both charges.
The document Ms Evans signed off on answered that "there is no documentation indicating this".
"Our expectation when Mr. Thomas was brought into custody is that he'd be kept safe".
Thomas' family said he was having a mental breakdown at the time when police arrested him on April 14, 2016, after he shot a man near his parent's house and then fired a gun inside a casino. The newspaper had previously identified a 2011 case in which an inmate died of "complications of psychotic disorder" after staffers turned off the water in his cell. During the same year as Thomas' dehydration death, a baby died inside the facilities due to staff refusing to assist a detainee who was in labor.
Three staffers at the jail formerly run by Trump-loving Sheriff David Clarke have been charged for their role in the death of a prisoner who died from dehydration back in 2016.
Three jail staffers charged in inmate's dehydration death
Thomas' case wasn't the only time an inmate was punished by being deprived of water.
The Milwaukee County Jail has a history of failing to fix "appalling" conditions in accordance with an agreement among the county, the American Civil Liberties Union of Wisconsin Foundation and the Legal Aid Society of Milwaukee.
David Clarke, a right-wing sheriff known for his advocacy of rough treatment of prisoners, resigned previous year after a highly controversial tenure as Milwaukee County Sheriff.
Sheriff Schmidt said the three guards who had been charged had been suspended.
"I will be very strong on my decisions if indeed those documents support what I believe they're going to show", Schmidt said. It is possible that they will face charges at a later date.
Sheriff Schmidt said the accusations against his employees were "horrific" and that "my heart bleeds" for Mr. Thomas's family.
Jurors had also recommended charges against four other staffers - JorDon Johnson, Thomas Laine, Dominique Smith and John Weber - but Chisholm concluded they shouldn't be prosecuted.
All three appeared in court Monday and remain free on bond. "To the family, I have nothing but deepest sympathies for their loss".More news: Maria Sharapova knocked out of Qatar Open in opening round
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