Transcript for A Culture of Police Speeding
Crossing the line continues. Once again, Matt Gutman, on the hunt for speeding cops, who kill. Reporter: So this guy's going well over 80 right now. So there I was humming down the highway in a dodge challenger, trying to chase down a speeding North Carolina state trooper. Guys, this guy's going 70 in a 45 right now. How did I get here? Well, it all started when we first saw this video. It's a Florida state trooper in hot pursuit of a motorist flying up I-95 at speeds up to 120 miles per hour. But this is no ordinary speed demon. It's a miami-dade police officer. It is a Miami police. Reporter: The cop ignores the trooper's lights and sirens, and tears across lanes of traffic. Finally, seven minutes later he pulls over. Believing that only a criminal in a stolen car could drive so recklessly, the trooper approaches with gun drawn. Put up your hands out that window right now! Put your hands out the window! Reporter: What's the big need for speed? Turns out, the cop was running late for his off-duty job as a security guard. I had to get there by 7:00 and I didn't think I was gonna make it. Reporter: And we discovered, this guy isn't some kind of lone wolf. All around the country families have learned the painful way that speeding cops can kill. To be clear, we're not talking about police responding to an emergency with lights and sirens on. And when cops just gun it, results can be lethal. Take a look at this. It's 2:15 A.M. On this Connecticut road. A Milford police department car speeding in a 40-mile-per-hour zone. Suddenly, another cruiser rockets past at 94 miles per hour and rams into a passenger car. Killed in the accident were two 19-year-old sweethearts. Ashlie Krakowski, a high school hockey star with dreams of becoming a nurse. And David Servin, a talented musician who planned to go to business school. When we found out what exactly happened, it was unbelievable. Reporter: Did it make it hurt worse once you learned that it was a police officer who hit them? I was disgusted that it was a police officer. You see them racing around all the time. And, you know, this time they didn't get away with it. Reporter: So, why do cops speed? Because they can. Reporter: Justin Hopson is a former New Jersey state trooper who wrote a book on corruption in his agency called "Breaking the blue wall." And when they're speeding, where are they going, home? Lunch, meeting another police officer. It's the mentality of "Hey, I have a badge and the ability to go as fast as I need to go." What's he doing? What's he doing? Reporter: The problem's gotten so out of hand, some motorists are striking back, catching speeding cops in the act. Here, a caravan of hot rods on a joyride down a New Jersey highway hit speeds over 100 miles per hour. Doing 100. A New Jersey state trooper suddenly appears, he's going to put a stop to this, right? Wrong. He shoots ahead of them to lead the way. He's going to give them an escort by state police! Reporter: That pied-piper of sports cars was suspended. This angry motorcyclist with a helmet cam turns vigilante and takes off after a fast-moving police cruiser just to prove how fast he's going. Folks, don't try this at home. I'm going 20 miles an hour over the speed limit right now. Reporter: But none of the highway video avengers can match Ron Carr of Raleigh, North Carolina. After getting his hair blown back by lead-footed lawmen once too often, Carr rigged his vehicle with cameras to expose what he calls rampant hypocrisy. Watch this guy. You or I would get a ticket for doing what he's doing right now. Reporter: Yes. They're fast and he's furious. Who's policing the police? What does it take for an officer to be charged? Reporter: Carr's now posting his greatest hits on, what else? His own youtube channel. I figured the more videos that I have, then folks will realize that it is a common problem. Reporter: But it's a problem that police departments seem reluctant to acknowledge. Going back to that terrible Connecticut crash, the officer involved was convicted and sentenced to ten years in prison, though he's currently free as he appeals. The families of those two young victims wanted to uncover the scale of the problem, so they sued the police, demanding to see all dash cam video from the previous two years. We wanted to know, was there a culture of speeding? Was this an isolated incident that you could forgive a little more easily? Reporter: The families did receive 500 dash cam clips, including footage of an officer on a call racing at 113 miles per hour in a 45 zone. He was suspended. But then, Milford pd claimed it accidentally deleted another 2,000 dash cam clips. 2,000 clips, an accident? The family isn't buying that. There appeared to be quite a culture of speeding to the extent that Milford finally destroyed the tapes. Reporter: Former trooper Hopson says it's almost unheard of for cops to crackdown on each other over speeding. If you do so, you're deemed a stool pigeon. And there's ramifications for doing that. Get out of the vehicle! Reporter: Want proof? Then turn back to that video of Florida trooper donna Watts. Remember she'd pulled over a Miami police officer, who was later fired from his department and is now trying to get his job back. But Watts says she was the one ultimately punished. After the incident she started receiving threatening phone calls and spotting strange police vehicles in front of her home. She's now suing the cops who were snooping on her, claiming the harassment made her life hell, prompting her to leave road patrol, even her home. Don't you think it's a little hypocritical that police officers go 80 miles per hour and pull someone over? What's the big hurry? We set up our speed trap just to find out who these speedy cops are and just where they're heading? Anything we purchase
This transcript has been automatically generated and may not be 100% accurate.