PLAINFIELD - A Plainfield family is filing a civil rights lawsuit against Middlesex County and Piscataway Township, stemming from the death of a 27-year-old prisoner who died of a broken neck while physically restrained at the Middlesex County Jail. And exclusive video of the incident, obtained by Kane In Your Corner, raises more questions than answers. The footage ends with David Yearby strapped into a chair, unable to move, but seemingly healthy, and offers no explanation for why he was found with a broken neck, while still in restraints, hours later.

Yearby went missing last Halloween. His mother says he suffered from severe bipolar disorder, so she was relieved at first to learn that he had been picked up by Piscataway police. Family members say they informed police of Yearby's mental illness and asked that he be sent to a mental health facility, but police reportedly said he would have to spend the weekend in jail first, after assaulting a police officer. It's not clear if word of Yearby's diagnosis ever made it to staff at the Middlesex County Jail, but based on his treatment, the Yearbys and their attorney believe it did not.

The exclusive jailhouse video shows Yearby caused a disturbance in the jail's medical wing, apparently using his hospital gown to clog his toilet. Officers then stormed the cell and subdued him, handcuffing him and covering his face with a hood to prevent spitting. The officers first took Yearby to the nurse's office so that pepper spray could be flushed from his eyes, then took him to a cell where he was forcibly placed in a restraint chair.

Veronica Yearby, David's mother, says she believes corrections officers should have realized her son was mentally ill, and treated him more humanely. "Looking at that video and picturing him in that chair and what he went through, it was so horrible," she says.

But the video may be most notable for what it does not show: how and when the fatal injury was sustained. As the video ends, Yearby can be seen strapped in the chair and being examined by the jail nurse. He is responsive to questions and appears capable of moving his head and all four extremities. "Something happened after he got into that chair," says Gregg Zeff, the attorney representing the Yearby family in their civil rights case.

A Middlesex County spokesperson says the county is unable to comment on Yearby's death, because the county has a policy of not discussing matters that are under litigation. The Middlesex County prosecutor investigated the case earlier but declined to press charges, citing an inability to prove who caused the fatal injury. Yearby's mother admits "I may not ever find out what really happened," but says she hopes her lawsuit prompts county jails to change how they treat mentally ill prisoners in the future.