Newly released documents detail how a Colorado State Patrol trooper briefly chased an off-duty Denver police officer near Golden in October, how investigators used cell phone location data to track the officer’s speed, and the charges he now faces.

Christopher Thomas, 29, was arrested on Friday and released later that day on a $5,000 cash or surety bond. An arrest affidavit obtained by CBS News Colorado on Monday shows that the arrest was connected to a brief Oct. 23 chase involving a state trooper on Highway 58 just west of Golden.

Around 11:30 p.m. that night, a state trooper parked on the shoulder of the highway clocked a Dodge Ram pickup truck at 102 mph in a 65 mph zone, according to an arrest warrant. The trooper chased the truck with his lights and sirens on and got a partial license plate number when they got to eastbound Interstate 70 near Kipling Street in Wheat Ridge. At that point, the trooper said he and the truck were going 90 mph.

The trooper said traffic was “moderate” and described the driver as “reckless.” When he got behind the truck, it “accelerated aggressively.”

“The Trooper initiated a short pursuit, but speeds exceeded 100 miles per hour, and due to moderate traffic on Interstate 70, the Trooper discontinued the pursuit,” CSP said in a news release on Monday.

Dispatchers ran the partial license plate and vehicle model, which brought up Thomas, according to the arrest warrant. Troopers parked on his street, and when Thomas returned home, he saw the troopers and allegedly fled, losing the troopers.

Learning the identity of the driver, CSP and several Denver police officers contacted DPD’s internal affairs unit, who requested that Thomas come into DPD headquarters. He did, having arrived in the same truck he allegedly fled troopers in, according to the arrest warrant.

After being read his Miranda Rights, Thomas requested to speak to an attorney, but agreed to let investigators search his personal cellphone for location data, calls, and text messages. Investigators say they were unable to find any evidence through a manual search of his phone and returned it to Thomas while they waited for a call detail records, or “CDR” warrant.

CDR warrants allow law enforcement to get cellphone metadata from cell service providers, which shows things like location data, who someone calls or is called by, when, and how long they’re on the phone for.

The warrant was approved and signed by a Jefferson County judge on Nov. 7 and sent to Thomas’s cellphone carrier. On Nov. 21, the company returned the requested CDR data to DPD, whose investigators then pored through that information using a program called Nighthawk on Dec. 3.

The location data, coupled with the time Thomas was allegedly at those locations, led investigators to estimate the speed at which he was traveling and placed him at locations consistent with the pursuit, according to the arrest warrant.

Two days later, Thomas was arrested on suspicion of felony vehicular eluding creating a substantial risk of bodily injury and misdemeanor reckless endangerment.

Thomas joined DPD in 2021 and was most recently assigned as a patrol officer to District 1, in the northwest part of the city, according to the department. He was suspended without pay because he’s facing a felony charge. If convicted of the felony, he’d lose the ability to be a law enforcement officer in Colorado.

“The Denver Police Department is committed to transparency and accountability,” the department said in a statement on Friday. “When a Denver Police officer is arrested, DPD works to proactively share information in a timely manner, when possible. As with all arrests, the suspect is innocent until proven guilty.”

DPD says it will conduct an administrative review of Thomas’s alleged actions after his criminal case concludes.

He has not yet formally been charged. He’s due back in court on Monday.

Reached by phone on Tuesday, Thomas’s attorney declined to comment on the case while it’s ongoing.