A lawsuit against a Colorado state trooper will continue after a judge ruled he had no reasonable belief that a fleeing suspect posed an immediate threat in the fatal 2018 shooting of 19-year-old Ryan Millsap.

U.S. District Court Judge R. Brooke Jackson refused to dismiss excessive force claims against Trooper Gregorio Retana, even though the First Judicial District Attorney’s Office previously determined his actions were not criminal.

Based on the allegations in the lawsuit, Retana and other officers were not in danger, nor was there an indication that Millsap had a gun.

“Mr. Millsap did not use physical force against the officers or engage in any combative struggle or resistance that would merit deadly force as a means to stop an escape,” Jackson wrote in a July 29 order.

According to the lawsuit from Dianna Millsap, the mother of Ryan Millsap, Retana came across a Toyota 4Runner on the side of Highway 6 on the night of Nov. 4, 2018.

Ryan Millsap was in the driver’s seat, and a 16-year-old runaway was in the passenger’s seat, both asleep. Retana learned the vehicle had been recently reported stolen, and that the driver was the suspect in a recent attempted murder in Lafayette. Retana requested the assistance of other officers.

When Jefferson County and Golden authorities arrived, they shouted for Millsap and his passenger to wake up. Millsap did so, started the 4Runner, and allegedly moved slowly around the officers without driving directly at them.

After the 4Runner had passed them — still driving slowly — Retana allegedly fired into the vehicle. A sheriff’s deputy followed suit.

A bullet struck Millsap in his head and he subsequently died. News reports at the time suggested Millsap died after driving down an embankment in Clear Creek Canyon.

The office of then-District Attorney Peter Weir investigated the incident and concluded Retana had reasonably feared for his and his fellow officers’ lives in shooting Millsap.

The report described that Millsap “appeared to reach down for something” before driving the 4Runner toward a patrol car.

“In the final analysis, Ryan Millsap’s failure to follow police commands and his efforts to escape in the manner described created this extremely unfortunate situation,” Weir wrote.

Dianna Millsap sued the officers involved, as well as Jefferson County, the sheriff’s office and Colorado State Patrol.

The defendants asserted qualified immunity, a judicial doctrine that shields government workers from liability unless they violate a clearly-established legal right.

Excessive force claims implicate the Fourth Amendment, which prohibits unreasonable searches and seizures. Prior court decisions have established that the use of deadly force to apprehend someone qualifies as a seizure.

Jackson found that even though Millsap would have been headed toward other officers up the road who were blocking traffic, the 4Runner did not seemingly endanger Retana himself.

“Officers shot Mr. Millsap in the back of the head, and only began shooting once he had already passed them,” the judge noted in denying Retana qualified immunity.

Jackson did, however, grant immunity to the Jefferson County sheriff’s deputy who also shot at Millsap. Jackson explained that an officer would have trouble distinguishing where gunshots were coming from, and Retana shot reasonably prompted the deputy to join in.

The government argued that Millsap did, in fact, drive “in the direction of the officers,” and said that courts have deemed the use of lethal force constitutional in those situations.

“It is beyond dispute that Mr. Millsap refused to exit the car and surrender, actively attempted to evade arrest, and accelerated in the direction of the officers,” the Colorado Attorney General’s Office wrote to the court.

It also accused Dianna Millsap of offering “speculation and self-serving proclamations to second-guess [officers’] decisions.”

In the district attorney’s review, Millsap’s passenger said Millsap had started by driving at the police officers, which is when they fired at the car.

But the deputy who shot after Retana said the 4Runner had cleared him “by a few feet,” and did not view the vehicle as a threat.

A second deputy and a Golden police officer also did not fire, as they did not fear for their lives.

Retana, in his interview to investigators, said he was worried for the safety of the deputy who was feet away from the car. Millsap could “potentially come at us” and “potentially shoot us,” Retana said.

The investigation noted that Retana had not communicated his position clearly to the other officers on the scene, and that Retana admitted he was inexperienced with this type of operation.

Dianna Millsap’s attorneys derided the district attorney’s inquiry, seizing on the fact that Retana and the deputy were not immediately interviewed and instead had the benefit of legal counsel.

“Properly cautious and properly trained officers would not have used deadly force in the situation that lead to the death of Ryan Millsap,” the lawsuit alleged.