According to his family, Ellis was trying to get his life on track in 2015, following a string of run-ins with the law. As Ellis' brother, Garrett Ellis, explained, Terral had racked up convictions for drug possession and driving with a suspended license, among other issues.
In October of that year, Terrall went to the Ottawa County Jail, in Miami, Oklahoma, to turn himself in to face DUI charges, for which he had an outstanding warrant. Video footage of Ellis' entry into the facility show a man who seemed to be perfectly healthy.
Twelve days later, the 26-year-old was dead.
What happened in those interim two weeks remains a matter of intense dispute in the northeast Oklahoma community.
According to Ellis' family, the young man came down with an illness while incarcerated in the facility. Over the course of the 12 days he was inside, the family says Ellis repeatedly asked for help, even to the point of screaming in agony. They say staffers not only ignored his pleas, but mocked him as they passed by his cell and did nothing.
After less than two weeks in the jail, the seemingly healthy young man died of pneumonia and sepsis.
Now, surveillance-camera footage of some of Ellis' time in the jail has been revealed, and it appears to corroborate the family's claims that Ellis' pleas and screams were ignored.
You can key scenes from that surveillance footage in the video below, but be warned: it contains content that may be disturbing to some viewers.In one clip, an employee identified as former jail nurse Theresa Horn can be heard allegedly cursing at Ellis and mocking him.
"I'm sick and tired of f****** dealing with your ass. Ain't a damn thing wrong with you," she allegedly said, four hours before he was found unresponsive in his cell.
Ellis family attorney Dan Smolen, who is representing the family in a wrongful death and negligence lawsuit against the jail, says that the people who allegedly ignored Ellis' please belong in jail themselves.
"I think that the entire jail staff should have been charged with some form of manslaughter," he said.
In a statement, Horn's attorney says that "the videos do not show the complete picture and are only one piece of potential evidence."