Antoine Wallace was in the midst of serving a 218-month sentence at the United States Penitentiary in Florence when he stood before a judge earlier this month. Now, he'll be behind bars for a lot longer.

The 39-year-old career criminal has been sentenced to another sixty years in a horrific attack on prison personnel, including Jason Unwin, seen here, that's detailed in a report on view below.

Wallace had first come to Florence in 2008, after being convicted in regard to a bank robbery in the District of Maryland. Two years later, on December 21, 2010, he went to a scheduled meeting with a pair of correctional counselors, Unwin and Jay O'Niel. At the get-together, according to the sentencing statement filed by Colorado's U.S. Attorney's Office in the state's U.S. District Court branch, Wallace was told by O'Neil that he would be losing his job as a unit orderly.

To understate the case considerably, Wallace didn't take this news well. He's said to have become so angry and disruptive that Unwin and O'Neil quickly brought the meeting to a close. But that wasn't the end of Wallace's display. He allegedly stormed out of the office into a common area of the housing unit, pulling off his outer shirt as he walked. After bounding up some stairs to drop off this garment in his cell, he then marched back to the office, hitching up his pants as he went, removed his glasses and handed them to another inmate, and then slugged O'Neil in the face.

It was quite a punch: O'Neil instantly lost consciousness and collapsed in a heap. Unwin reacted by trying to take a defensive posture, but it didn't help. Wallace reportedly socked him in the face, too, causing him to fall on top of O'Neil's body.

At that point, the inmate left the office, closing the door behind him. But Unwin wasn't out cold -- not yet, anyway. A moment later, the report says, he emerged from the office, blood dripping from his face, and after adjusting his glasses, he tried to radio for help. Wallace wasn't having any of that, however. After seeing that Unwin was ambulatory, he launched another attack, striking the counselor in the face with both fists before pushing him down. Unwin's head smacked the concrete floor, knocking him out. His body lay in a large pool of his own blood.

O'Neil wound up suffering the least serious injuries of the two -- some disorientation from the blow to his head, plus a torn lip and soreness to his teeth and tailbone that let up after a month or so. But Unwin, a sixteen-year employee of the federal prison system, was in much worse shape. Personnel who first came to his aid thought he was dead, the report maintains; he had to be identified by his name tag because the beating had left him almost unrecognizable. He was transported to a nearby hospital via a Flight For Life chopper and remained in critical condition for days afterward. He was finally released from the hospital three weeks later, but in the nearly two years since then, he's continued to suffer from the after-effects of traumatic brain injury.

Continue to read more about the Antoine Wallace case and see the complete sentencing statement. More details about Unwin's condition can be found in "Plan to cut benefits for injured federal workers stirs concern," a March report by The Center for Public Integrity. As of earlier this year, he still didn't have full range of motion in his right shoulder and suffers from short-term memory issues and irregular sleep. He's been diagnosed with post-traumatic-stress disorder and is considered at-risk for seizures. As such, he has been unable to work since the attack.

Fortunately, Unwin is covered by the Federal Employees Compensation Act of 1916, which secures 75 percent of his previous salary tax-free. But this benefit was endangered at the time of the article by a provision tucked into a postal-reform bill. That measure ultimately passed the Senate, but as of last month, it was stuck at the House level and considered unlikely to break out of the logjam until after the November election.

Meanwhile, the authors of the sentencing statement sought the harshest possible sentence for Wallace, based not only on Unwin's injuries, but also the inmate's own past.

"Defendant Wallace demonstrates an extreme danger to the public," the report allows. "He has a prior history of egregious violent acts, including assaulting a woman who was six months pregnant and shooting at a victim several times with a shotgun. Nor does Wallace need a weapon (besides his own fists) or prior motive in order to effect grave harm on others."

In addition, Wallace is said to have "demonstrated his inability to control himself...throughout these trial proceedings."

As such, prosecutors requested a sentence of sixty years -- and they got that and a little extra. In addition to the six decades in stir handed out by U.S. District Court Judge Christine M. Arguello, Wallace will be under a supervised release order for three years following his release.

Of course, if he completes the entire sentence, he's unlikely to need much supervision, being as he'll be on the cusp of his one-hundredth birthday. But it's the thought that counts.

See the complete sentencing statement here.

More from our Colorado Crimes archive: "Gary Lee Davis: Colorado's last volunteer for the death penalty."

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