The family of Deven Guilford, an unarmed Michigan teen who was shot seven times by an Eaton County sheriff's sergeant and left dead in a roadside snowbank, filed a wrongful death lawsuit this week.

The family alleges that Sgt. Jonathan Frost used excessive force and unconstitutionally violated Deven's privacy during the February 28 traffic stop.

Deven was pulled over after flashing his high beams at the sergeant's patrol SUV, and both body cam footage and Deven's cell phone recording of the encounter shows the teen arguing with the sergeant, explaining that he was simply trying to notify the driver that his own brights were on.

Warning: This video includes disturbing content.

In the video, Deven refuses to give the sergeant his ID and attempts to make a call before Frost pulls him from the car. The sergeant then orders Deven to lay on the ground, kicks the cell phone out of the teen's hand, and uses his stun gun in an attempt to arrest him. A struggle ensues and the video goes dark. Moments later, several gunshots ring out and Deven is heard screaming.

"The Ford Explorer had 'improperly bright or misaimed headlights' and Frost had stopped two other drivers for flashing their lights at him that night," the New York Daily News reported.

Frost claims that the teen attacked him, prompting him to use lethal force, but it is unclear what happened based on the video. He shot Guilford seven times in self-defense, according to the Eaton County Sheriff's Office. Eaton County Prosecuting Attorney Douglas Lloyd agreed that the use of force was justified.

"After considering all of the evidence from this case as applied to current Michigan criminal laws, I have determined that charges will not be issued against Eaton County Sheriffs Sgt. Jonathan Frost in the shooting death of Deven Lee Guilford for the reason that the evidence supports that Sgt. Frost used his firearm within the limits of Michigan's self-defense law," Lloyd wrote in a statement.

But the teen's family doesn't accept the official account of the shooting, finding it difficult to believe that the 17-year-old, who they say had never been in a fight, would violently attack a law enforcement official.

"Deven's tragic and totally unnecessary death represents a disturbing trend of demanding 100 percent compliance with police authority, coupled with zero tolerance of risk of harm to police officers," the family's lawyer, Cynthia Heenan, said in a statement. "Whatever happened to protect and serve?"

Before being pulled over on February 28, Guilford was on his way to his girlfriend's house after playing basketball at a nearby church, according to police.

Eaton County Sheriff Tom Reich issued a statement on the fatal shooting on Friday, writing that the "incident is a tragedy for everyone involved, certainly for the Guilford family, but also for Jon Frost and all the men and women of the Eaton County Sheriff's Office and the entire Eaton County community."

"One of my top priorities as Eaton County Sheriff is to always evaluate and improve the services that my office delivers to the public. As a result of this incident, we have reviewed the training provided officers in the use of the Taser, given increased emphasis to defensive tactics training, reviewed and continued training regarding the positioning of vehicles during high risk traffic stops, and reviewed and continued to emphasize training concerning officer communications with the citizens they encounter to increase the instances of voluntary cooperation following a decision to make an arrest."