RAW police dash cam:Trapped inside a car traveling at more than 75 mph through a Denville neighborhood, officer Richard Byrne gave the driver one final order to stop.The driver accelerated and Byrne, believing he was about to die, did what he felt he had to do: He pulled out his gun and fired five shots into Ruben Martinez's torso."I can't feel my legs," Martinez shouted as his 2001 Ford Mustang GT Bullitt, at that point accelerating to 89 mph, veered off Franklin Road, went airborne, crashed through a concrete retaining wall and into an above-ground swimming pool.Martinez died a short time later.A special Morris County grand jury found Byrne's use of deadly force against the 21-year-old Martinez on June 26 was justified, and issued no criminal charges against the 14-year veteran, Morris County Prosecutor Robert A. Bianchi said Thursday.Byrne had the right to use deadly force to prevent severe injury or death to himself or others, and "I think that's exactly what officer Byrne did," Bianchi said.During a news conference in Morristown, Bianchi outlined the findings of his office's investigation and showed chilling video that preceded the shooting and was recorded by a camera inside Byrne's patrol car and another in officer Daniel Fernandez's vehicle. Audio was also recorded from wireless microphones the officers were wearing.The video starts with Martinez speeding off onto eastbound Route 46 at about 2:14 a.m. after Byrne tried to stop him for going 57 mph on Franklin Road, where the speed limit is 25 mph. Martinez's car can be seen whipping around short blocks, ending up back on Franklin Road, where it spins almost 180 degrees and stalls, partially on the sidewalk."Out of the car! Out of the car! Out of the car! Get your hands up!" Byrne, his gun drawn, shouts as he approaches and opens the passenger side of the Mustang. Bianchi noted Martinez's finger was not on the trigger and that when Martinez ignored his commands and tried to speed away, Byrne re-holstered his gun and leaned into the car to grab the keys.The video shows the Mustang lunging forward as Martinez revs the engine. Byrne is seen kneeling on the passenger seat, struggling with Martinez. Toxicology tests later showed Martinez's blood-alcohol level was 0.16 percent, twice the legal limit and that he had marijuana in his system, the prosecutor said.On the video, Fernandez, who was also involved in the chase, comes up on the driver's side of the Mustang and bangs Martinez's head against the door frame several times. Martinez takes his hands off the steering wheel. Bianchi said Byrne, believing Martinez was going to comply with orders, told Fernandez to let go of him.But Martinez shifts the car into gear and it lunges forward. Byrne struggles to take it out of gear and grabs the keys, but Martinez speeds away, the video shows. The passenger door slams shut with Byrne inside."He's leaving with Richie in the car!" a frantic Fernandez can be heard telling headquarters.Martinez drives faster and faster, ignoring Byrne's orders to stop, Bianchi said.According to Bianchi, Byrne thought, "I'm going to die. I'm going to die tonight." In the two seconds it took Byrne to fire five shots - all of which hit Martinez - the speed of the vehicle increased from 75 mph to 89 mph, the prosecutor said.Just beyond Fernwood Trail, the car veers off the road and crashes into the swimming pool. On the video, Byrne can be seen emerging, breathing heavily and bending over with his hands on his thighs, sloshing through the spilled pool water."Did you shoot him?" Fernandez asks, Byrne said yes, eliciting an expletive from Fernandez. One of the bullets pierced Martinez's heart, Bianchi said.Martinez's family viewed the video two weeks after the shooting. Their attorney, Scott Leonard, contends Byrne did not need to shoot Martinez, who was unarmed."There were other reasonable means available to officer Byrne to prevent the shooting," Leonard said.Byrne violated policies and procedures for a vehicle stop and pursuit, Leonard said, adding the Martinez's family has filed a notice of intent to sue the Denville Police Department for excessive force, negligence and civil-rights violations.Martinez's mother, Maureen Miles of Rockaway Township, could not be reached for comment Thursday. Martinez, a 2005 graduate of Morris Knolls High School, was working as a mechanic in Texas but had returned to New Jersey for his brother's high school graduation.Denville Police Chief Christopher Wagner said Byrne, 36, was relieved to be exonerated, "but he will always feel this sadness for the rest of his life.""Regrettably, lives have been changed forever," Wagner said, noting the shooting has taken a toll on his officers as well as the Martinez family. "I want to send my condolences to the Martinez family on behalf of the Denville Police Department," Wagner said.Byrne has not returned to work because of a shoulder injury he sustained in the incident that will require surgery, Wagner said.Byrne did not want to speak to the press, but his attorney, Anthony Pope, said he was doing "okay.""No officer, when he goes out on patrol, is hoping for this type of situation," Pope said. "He encountered a situation in which he had to act. He showed incredible restraint until the point in which he no longer had a choice and he used deadly force."Bianchi said he stuck to his word and his office conducted a thorough investigation, uninfluenced by sympathy or prejudice, to uncover the truth."I realize that in a case of this nature, there are no winners or persons who can claim victory. The fact is that a tragic loss of life has occurred and for that there is no turning back or replays allowed," he said.