(CNN) Allen Capers knew he had done wrong and was willingly serving his time for armed robbery and kidnapping at Turbeville Correctional Institution in South Carolina, his mother, Debra Capers Dickson, said at a news conference Thursday.

But according to a lawsuit against the state's Department of Corrections, his life was cut short when he was stabbed inside his cell, dragged into the prison yard by correctional officers and left to die. The suit says prison personnel walked by him, leaving him to bleed to death on New Year's Eve 2017.

"Allen did something wrong," Dickson said Thursday. "But he wanted to do his time because he knew he did wrong. He wanted to make it right."

Capers' final moments were caught in disturbing surveillance footage obtained and released by the family's attorney, Justin Bamberg. The footage shows Capers struggling to get to his feet and repeatedly falling to the ground. Over the course of the video, Capers was approached by correctional officers several times, but he was not given medical treatment.

"It's not a death sentence just because you go to prison," Dickson said. "You go to prison, you get reformed and you come back into society."

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