(Photo courtesy of Colorado Department of Corrections)

In 2008, Evan Spencer Ebel pleaded guilty to assaulting a prison guard, resulting in four additional years in prison, to be served after he finished the eight-year sentence that originally put him in jail back in 2005.

But the court clerk recorded the additional four years to be served “concurrently,” or at the same time as his original sentence, which is the information that went to the state prisons, a statement from the 11th Judicial District said.

The Salt Lake Tribune reported that the judge did not say the sentence was meant to be “consecutive,” or added onto Ebel’s current one.

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Ebel spent much of his time behind bars in solitary confinement and had a long record of disciplinary violations. Records show he joined a white supremacist prison gang, known as the 211 crew, the Associated Press reported.

Ebel was shot dead two months later after a shootout with Texas authorities and the gun he used was the same one that killed prisons chief Tom Clements two days earlier, said the Tribune.

Authorities believe Ebel also killed Domino’s deliveryman Nathan Leon in Denver, and investigators recently found bomb-making materials in Ebel's car.

"The court regrets this oversight and extends condolences to the families of Mr. Nathan Leon and Mr. Tom Clements," said in a statement signed by Charles Barton, chief judge of the 11th Judicial District, and court administrator Walter Blair.

Corrections officials say they had no way of knowing the plea deal was supposed to keep Ebel in jail for years longer, as the missing “concurrent sentence” made it impossible for state prison officials to know Ebel had signed the plea agreement agreeing to serve an extra sentence. 

"It sounds like a horrific oversight," said Pueblo County Commissioner Buffie McFadyen, who is executive director of the correctional officer group Corrections U.S.A.

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Colorado court records show he was arrested at least seven times between 2003 and 2010 for crimes including burglary, weapons possession, assault, menacing, robbery and trespassing, said the Chicago Tribune

“Had the plea agreement resulted in a correct sentencing order, then Ebel would still be in prison today and Tom Clements and Nathan Leon would still be alive,” said attorney Scott H. Robinson, a legal analyst at KUSA-TV in Denver.

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