MINNEAPOLIS (WCCO) — When 34-year-old Ryan Larson was released from custody, Stearns County officials said they lacked evidence of probable cause. At that moment, the Nov. 29 killing of Cold Spring police officer Thomas Decker became an even more troubling mystery. If Larson wasn’t responsible for the cold-blooded killing, who was?

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On Friday, new details began to emerge in the moments leading up to that fateful night. Court documents contain a narrative describing what part-time officer Greg Reiter saw and how he responded.

A Troubling Story

“None of it makes any sense,” says Minneapolis attorney Joe Friedberg, who now represents Larson.

Larson is the Cold Spring resident who police were asked to check on when relatives feared for his safety, hours leading up to Decker’s death.

In his only television interview, Larson spoke to WCCO-TV and denied any involvement in Decker’s killing.

When asked if he had anything to do with the murder, Larson quickly said: “Absolutely not.”

Contrary to early reports, it was Decker who was second on the scene. Reiter, his fellow officer, was still sitting in his squad outside Larson’s building when Decker pulled up at 10:45 p.m., got out of his squad car and walked towards Larson’s apartment.

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Reiter told investigators that he heard two loud “bangs.” Seconds later, he observed a white male, about six feet tall, wearing a dark stocking cap, hooded sweatshirt and jeans standing near Decker’s car, pointing a handgun in a shooting position.

At that point, Reiter said he put his squad car in reverse and backed out of the parking lot. While backing away from the killer, he says he observed Decker’s body on the ground and the killer walking away to the west.

That statement troubles Friedberg, Larson’s attorney.

Friedberg had this to say about it: “[Reiter] claims he retreated as fast as he could and then saw the man with the pistol walk away. We’re in Cold Spring. Where could he have gone? And why wouldn’t he have followed him with his car while he was calling for help?”

Investigators later revealed that Decker was killed by a 20-gauge shotgun slug.

Nothing in the probable cause filing (the court document mentioned above) makes any mention of a weapon other than a pistol.

We asked the Bureau of Criminal Apprehension for comment on the details in the court filing. They told us they will not discuss details of an active and on-going investigation.

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It’s unknown if Reiter remains on patrol or if he was placed on leave pending the investigation.