Nearly three years ago, Chris Prevette, a detective sergeant with the Michigan State Police Computer Crimes Unit, made the unprecedented decision to access the data from a stolen vehicle. It’s not that investigators hadn’t previously obtained GPS logs, which in this case proved the car stopped twice at an RV dealership miles away from where it was reported taken, but there’s so much more data collected by vehicles nowadays. The various built-in systems revealed when the car was parked and even when the driver’s door opened and closed, according to a report by NBC News. This information helped Prevette narrow the suspect pool to a male who worked at the RV dealership, and who was ultimately convicted.

“I wasn’t surprised to see the GPS information. But to see things like when the vehicle shifts, when the doors are open, phones connecting, text messages — there was so much more than I expected there to be,” said Ryan Pieske, a detective on the case.

Law enforcement agencies all over have quickly adopted digital vehicle forensics as a high-tech investigative tool. As auto manufacturers add electronic systems and devices to all different makes and models, vehicles have turned into rolling databases, storing all sorts of digital information. First, there is the telematics system, which maps out navigation, speed, and acceleration and deceleration. It also captures engagement patterns of lights, seat belts and even when doors are opened and closed. Then there’s the infotainment system, which contains data from synced phones and other connected electronic devices, like call logs and text messages, as well as voice commands and web histories.

“I’m sure everyone is aware of how much forensic data is on the phone. What people don’t realize is a lot of that is being transmitted to a car just because you register the phone with the car,” Lam Nguyen, director of the Defense Cyber Crime Center, a federal forensic laboratory and training center, explained to NBC News. “If you’ve committed some heinous crime and we can’t get into your phone, we can get peripheral data that has been synced to your car. The contact list, calls made, text messages. In almost any criminal investigation, communication with the victim or co-conspirators is hugely important. Taking that with the telematics you get — how many people were in the car, how many doors opened — and it all paints a strong picture.”

Encryption on smartphones often complicates law enforcement’s access to devices and their data, but neither telematic nor infotainment systems in cars contains similar security measures, so access is much easier to crack. Also, NBC News reports no federal law regulates what type of data automakers can collect or what they do with it, including aiding police investigations. The Driver Privacy Act, passed in 2015, only addresses a vehicle’s event data recorder, the system that records information before, during and after a crash.

While privacy advocates express concerns about law enforcement access to vehicle data, the trend to use it as an investigative tool seems to be gaining acceptance as cops rely on it to close cases.