CLEVELAND, Ohio -- The estate of a man shot and killed in front of his girlfriend and children by a Strongsville police officer filed a civil rights and wrongful death lawsuit Thursday that says the man never posed a threat to the officer.

Officer Jason Miller shot Roy Evans Jr., 37, after Evans' Ford Econoline van stopped following a 14-minute chase. Evans was unarmed and shot while sitting in the driver's seat.

Miller later told criminal investigators that he feared for his life because he believed he saw Evans reaching for a weapon. Investigators searched the van and found no weapons inside.

Miller's first shot happened about 4.7 seconds after getting out of his cruiser, according to records from the Ohio Bureau of Criminal Investigation. He said he yelled at Evans to comply before firing the first shot and fired a second shot about two seconds later, the records say.

The lawsuit, filed in federal court in Cleveland, says Evans "posed no threat to the officers or anyone else" when Miller fired. Joseph Scott, who filed the lawsuit along with attorney Marcus Sidoti, said Miller gave Evans no opportunity to move before he opened fire. Sidoti said Miller immediately fired upon getting to the van's driver-side door.

They questioned the officer's assertion that he saw Evans make a move. Dashcam footage showed Evans smoking a cigarette after the van stopped, they said.

(You can read the full lawsuit here or at the bottom of this story. Below is a video of a news conference held Thursday afternoon by the attorneys.)

Watch as attorneys hold a news conference on the fatal shooting of Roy Evans Jr. by Strongsville police Posted by cleveland.com on Thursday, January 18, 2018

"I don't know why an officer would have thought that he was doing anything else," Scott said at a news conference Thursday.

The suit was also filed on behalf of Evans' longtime girlfriend Amanda Pauley and her three children, who were between the ages of two and 15 years old when the shooting took place. Evans was the father of two of the children.

The lawsuit says Miller fired "with complete disregard" and needlessly put the others in the van in danger.

The shooting marked the fourth time Miller has been involved in a police shooting. He previously shot another unarmed suspect, the suit states.

The lawsuit also names a sergeant on scene and retired police chief James Kobak as defendants. The suit seeks an unspecified amount in damages for excessive force on the part of Miller and Stronsgville police during the chase and shooting.

Scott, who represents Evans' surviving loved ones, said they are "literally trapped in a nightmare that I don't know that they'll ever get out of."

A phone call left for the Strongsville police chief was not returned.

A Medina County grand jury cleared Miller of criminal wrongdoing in August.

Evans was driving was his family home after finishing a carpet installation job and a Strongsville police officer started pursing him because the van's headlights were off, according to BCI agents. Evans suffered from unspecified mental illnesses and Pauley tried to get him to stop during the chase.

Evans refused, agents say. He rammed two police cruisers, including Miller's, during the chase, the records say. Police put out spike strips that popped the van's tires and then rammed the van to disable it.

Miller told investigators that he ran up to the van yelling for Evans to show his hands. He said he could see both of Miller's hands while running up to the van; one was on the steering wheel and one on the gear shift.

As Miller approached, he claimed he saw Evans drop his right hand, according to BCI.

"It was clear that this was going to be a fight and I thought for sure that he was coming up with a weapon," Miller said, according to BCI. "So I took one shot at his chest hoping that would stop, actually I was quite surprised to find that he did not stop."

BCI agents noted that no dash-cam videos showed exactly what Evans was doing inside the car. Pauley told agents that Evans didn't have enough time to say anything before Miller shot him.

The lawsuit says Strongsville police's ramming of Evans' van constituted excessive force.

"It's totally unnecessary in this case," Scott said. "The van was completely disabled, essentially by the stop strips. The tires were blown out. That van wasn't going anywhere."

After Evans stopped, a Strongsville supervisor told all officers to stay in their cars and "follow felony call out procedures" rather than rush the van, the suit states.

"Despite the supervisor's order, Officer Jason Miller and another Strongsville officer immediately exited their vehicles and rushed Evans' van," the lawsuit says.

The case is assigned to Chief U.S. District Judge Patricia Gaughan.

This article was correct to reflect the nature in which Miller was involved in four police shootings.

If you would like to comment on this story, please visit Thursday's crime and courts comments section.