With his gun drawn, a Surprise police officer investigating a stolen license plate jumped into a suspect's vehicle last year and fatally shot the 20-year-old man behind the wheel.

Now, the man's family is suing for what they argue was the officer's use of excessive, negligent force.

An attorney representing the family of Derek Adame filed a wrongful-death lawsuit last month against the Surprise Police Department, the city and two officers involved in the Nov. 26 shooting.

A copy of the lawsuit, body-mounted camera footage and police records obtained this week by The Arizona Republic shed light on a suspicious-vehicle call that resulted in a police officer being partially dragged by a vehicle and a young father being shot dead the weekend after Thanksgiving.

"It's the family’s belief, and my belief as well, that the evidence will show that the shooting was out of policy, that it was a negligent shooting," said Anthony Ramirez, the family's attorney who filed the lawsuit, in an interview this week with The Republic.

A stolen license plate

Though the circumstances are somewhat unclear, reports suggest Adame was sleeping in his sedan in a southwest Surprise neighborhood when the officer approached at 12:48 a.m.

Officer Joseph Gruver moments prior received reports of a suspicious vehicle in the area. That's when he spotted the white 2016 Nissan Sentra parked on the side of the road near the greenbelt.

A quick check of the vehicle's license plate returned a "stolen tag" alert. He activated his overhead lights, aired the stolen plate report over the radio for confirmation, and stepped out of his patrol vehicle.

As a second officer headed toward the scene, Gruver unholstered his gun and approached the car. He briefly waited at the passenger door before he opened it, identified himself as an officer and demanded Adame put his hands on the steering wheel, video shows.

Adame can be heard saying, "What the hell?" before replying to the officer's commands by saying, "Yes, sir."

More than a minute passed. Officer Shaun McGonigle arrived at the scene just in time for his body-mounted camera to catch Gruver entering the passenger side of the vehicle, all the while yelling for Adame to keep his hands on the steering wheel — an action Adame can initially be seen doing.

"I'm not doing anything wrong!" Adame said as Gruver gets closer.

Video from Gruver's body camera captured the frantic few seconds that followed before a pair of shots rang out and Adame slumped over the center console, his foot apparently hitting the gas pedal and briefly trapping the officer.

Gruver would later tell investigators his goal in entering the vehicle was to control Adame's right hand while the backup officer moved to the driver's side to help make the arrest, according to police reports. He said he shot as the vehicle sped away.

Ramirez and the family disagree with his account.

"Without any warning or legal justification, Defendant Gruver used willful, excessive and unreasonable force when he shot and killed Adame," according to the lawsuit. "Defendant Gruver's negligent handling of his firearm resulted in Adame sustaining fatal gunshot wounds to his right forearm, torso and right shoulder..."

MORE:Surprise police identify man killed during police altercation

Timing discrepancies

In the days after the shooting, Surprise police explained the fatal shooting by saying there was a struggle and concern that Adame was planning to drive away and purposely drag the officer.

That sentiment is chronicled in the 89-page police report detailing aspects of the incident. However, Gruver's statements to police do not exactly match what is clear on the body camera footage.

Gruver, according to police reports, detailed his thoughts to investigators as he entered the passenger side of the vehicle. He struggled with Adame, who Gruver says hit the accelerator. That caused him to get "sucked into" the vehicle, according to reports.

Video helps understand the rapidly evolving scene.

"Don't move!" someone shouts as Gruver gets into the passenger compartment.

"Stop the vehicle!" as the car slowly starts moving forward.

Pop. Pop.

The vehicle accelerated, dragging Gruver for approximately three seconds after the shots were fired and Adame hunched over.

"He said he remembered seeing houses and trees moving very quickly out of the corner of his eye," investigators wrote. "He said the vehicle's engine was revving very high as if it were pedal to the metal. Gruver said, 'At that point, that part of your head says, 'I'm gonna die here.'"

Seventeen seconds later, the vehicle can be heard crashing into a pickup truck parked down the street.

Officers approached the vehicle after the crash and attempted life-saving measures on Adame.

He was pronounced dead moments later.

Gruver's adrenaline was already heightened when he approached the vehicle that night, he told investigators.

Gruver said he didn't know if an armed burglar could have been in the area, potentially hiding in the greenbelt nearby. He — and officers across the country — was also on heightened alert after three ambush attacks on law enforcement officers happened earlier that week in Texas, Missouri and Florida.

A search of Adame's vehicle later revealed live ammunition, knives — including a small folding knife in his pocket — and drug paraphernalia consistent with heroin use, investigators wrote in their reports.

It is not clear whether he was under the influence of drugs at the time of the shooting.

MORE:Surprise police identify officer involved in shooting

A 'multi-million-dollar case'

In addition to claiming the incident was clearly excessive and negligent force, Ramirez called into question departmental protocols and training standards and highlighted a "supervisory liability."

Adame's death was "caused by the failure, negligence and carelessness" of the city "because it failed to properly hire, train and supervise the police officers it employs," according to the lawsuit. If Gruver was concerned about his safety, Ramirez says the officer could have de-escalated the situation by backing up, rather than entering the passenger side compartment at all — a tactic often discouraged in law enforcement circles.

"I am at a loss why Officer Gruver felt a need to jump into that vehicle,” Ramirez said.

McGonigle, the second officer, is also criticized in the lawsuit for not intervening sooner. Ramirez says the city's policies fostered the environment that led to shooting in the first place.

Gruver, who had been with the agency for one year, was placed on paid administrative leave immediately after the shooting, as is department policy in such cases.

He has since returned to duty, Sgt. Tim Klarkowski said, adding the professional standards unit is continuing its investigation.

Klarkowski declined to comment further for this story, saying it would be "inappropriate" due to the ongoing litigation. City officials with Surprise also declined the Republic's request for comment this week.

Attorneys for Surprise have until Oct. 23 to respond to the complaint, according to court records.

Ramirez, a former police officer, said the family is seeking an apology from police and justice for Adame, who left behind a young child. Regarding a potential settlement, Ramirez said it would "certainly" be a "multi-million dollar case."

“We think that the evidence will show that officer Gruver really overreacted."

Reach the reporter at jpohl@azcentral.com or follow him on Twitter: @pohl_jason

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