Keith C. Reilly, 42, was pronounced dead from suicide at Hackensack University Medical Center at 5:15 a.m. Sunday, Dec. 11, Sheriff Anthony Cureton said.
Officers assigned to the secure housing unit were conducting routine checks when they found Reilly suspended from the HVAC system by a bedsheet, the sheriff said.
He'd strangled himself, Cureton said, adding that an investigation was continuing.
Reilly, most recently of the Sussex County borough of Franklin, was arrested last week on charges of aggravated assault, making terroristic threats and unlawful weapons possession, records show.
Reilly made headlines in 2008 when authorities said he violated a protection order and held his then-wife at gunpoint with his service weapon in what was their home at the time in Sussex County.
Authorities said Reilly also head-butted the victim, bit her face and ordered her to slit her own wrists with a steak knife -- which they said he then threatened her with.
It was among several run-ins that Reilly had with the law after he was fired from the West Orange Police Department.
He took a deal from prosecutors, pleading guilty to making terroristic threats and criminal restraint.
A judge in Newton, in turn, later sentenced Reilly to 180 days in jail. He was also ordered to undergo anger management counseling, attend AA meetings and complete 100 hours of community service.
Reilly was also barred from ever getting another job in law enforcement in New Jersey.
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