RIFLE, Colo. — The 9th Judicial District Attorney has decided not to file criminal charges against a Rifle Police officer who shot and killed a suspect on a bridge overpass in August. 

A warrant was issued Aug. 3 for the arrest of 57-year-old Allan George in a suspected child pornography case.

Cellphone video shows George jog away from the officers moments before the shooting. He was shot twice in the back, according to an autopsy. 

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A decision letter from the DA's office says the use of force was justified as George was in possession of a deadly weapon and was acting erratically as he attempted to escape from law enforcement, presenting a dangerous situation for both officers and passersby. 

At around 7 p.m. on Aug. 3, Corporal Ryan and Officer McNeal with Rifle Police Department pulled George over near the intersection of Interstate 70 and Colorado State Highway 13, the letter says. 

George pulled over but refused to comply with the officers' orders, according to the letter. 

He eventually exited his vehicle, the letter says, retrieved a handgun, and began to threaten himself. 

A cell phone video recorded by a woman who was driving by shows George on a bridge overpass, on the opposite side of the guardrail, pointing a gun at himself. An officer is positioned behind his squad car's open driver's door holding George at gunpoint and shouting to "put the gun down." 

The letter says both officers are heard on audio recordings pleading with George as he repeats that "it's all over."

At about three-and-a-half minutes into the video, George comes back over the guardrail and starts to walk, then jog away from the officers. The cellphone video tilts down toward the ground and then a gunshot can be heard. The cellphone video tilts back up and shows George start to go down as another gunshot is heard. 

The letter says Ryan shot George in the back twice. He had the handgun in his pocket at the time. 

In his decision letter, the DA said the officers did not need to be directly threatened for the shooting to be justified. 

"Colorado law authorized a police officer to use deadly force upon another person when he or she reasonably believes it is necessary to defend himself/herself or a third person from what he or she reasonably believes to be the use or imminent use of deadly physical force," the letter reads. "Given the totality of the circumstances, an objective officer in Corporal Ryan's situation could have reasonably believed that Mr. George posed a significant threat of deadly physical force or of serious bodily injury to himself, a fellow officer, pedestrians, and/or other citizen motorists passing nearby especially as he was running toward the more concentratedly populated area of downtown Rifle."

You can read the full decision letter by clicking here.

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