Emme Hall/Roadshow

Your car knows a lot more about you than you think. It gathers all sorts of information, from where you've been to whom you've talked to and what music you like, and police are able to get all of that information without a warrant.

A Georgia Supreme Court case could change that. The American Civil Liberties Union argued Wednesday that police must obtain a warrant to access data collected by cars.

Police have been able to conduct digital searches in cars without a warrant because of a US Supreme Court decision in 1925, which established that police need only probable cause to search vehicles.

As technology's reach has expanded and changed the scope of how much personal information gets collected about a person, laws have lagged behind, leaving privacy rights in limbo for years. At the US borders, patrol agents are still able to search people's devices without a warrant, and it was only in 2014 when the US Supreme Court ruled that police need to get warrants to search our phones.

Last June, the US Supreme Court also ruled that police need a warrant to get phone location data, but there are still privacy challenges as more cases take on other ways technology can collect information.

The Georgia case could be another milestone in how the legal system deals with technology.

"The question of whether a warrant is required for roadside downloads is a really important question," a justice of the Georgia Supreme Court said during arguments on Wednesday.

The computer in a vehicle's infotainment system collects data including your location history, your phone contacts, songs you've listened to, video from inside the car and text messages. That's not including the data collected in the car's black box -- which is installed in 96% of cars.

Sometimes known as an event data recorder, the car's black box collects data on information like vehicle speed, seat belt use, braking, acceleration and more.

"This is yet another case that calls on a court to decide whether older doctrines from before the digital age should be extended to new kinds of intrusions on people's personal data," ACLU attorney Nathan Freed Wessler said ahead of the trial.

The case

The Mobley v. State case in Georgia stems from a fatal car crash in 2014. Police charged Victor Mobley with reckless driving, alleging that he drove at 97 miles per hour in a 45-mph speed limit zone.

He was found guilty in 2017 but appealed the conviction, arguing that police needed a search warrant to get the data from the car's black box because he "had a subjective expectation of privacy in the data," according to court documents.

Cars today aren't just metal boxes on wheels, they're roving computers that contain a stunning array of information. ACLU attorney Nathan Freed Wessler

Georgia's prosecutors said that downloading black box data at car crashes was a common practice, especially when it involves serious injuries or death. Law enforcement can obtain that data by removing the black box from the car and plugging it into their computers with a crash data recovery kit.

Police told the court that they didn't obtain a warrant because "we had the resources available at the time … to go ahead and just gather all the data that we could while we're on-scene."

This isn't the first time this issue has gone to trial, but it's the first time a state supreme court is looking at the argument. A court case in Florida in 2017 ruled that the Fourth Amendment protects people's privacy when it comes to their car's black boxes, while a case in New York and California ruled the opposite.

Data-driven

The black box data in cars doesn't just collect information for use in crash analyses, however. As those recorders are connected to a car's central computer system, it collects all the data that comes through, including personal information that Wessler argues is covered by Fourth Amendment safeguards against unreasonable searches and seizures.

The data stored in cars is sensitive and not encrypted, and unless courts establish legal protections, police can access it without a warrant, he added. And as car technology develops, it could include more information like video feeds and precise location history.

"All of that is now intermingled, and without a strong statement from this court that this type of data is different, we will be at risk of unconstitutional searches," Wessler said during arguments on Wednesday.

A group of 20 carmakers pledged to privacy principles that would give car owners a way to manage the data their vehicles collect on them and promised to obtain consent before using location and biometric data for marketing.

The trial that opened Wednesday could decide how easily police can obtain that data.

"The real issue is that cars today aren't just metal boxes on wheels, they're roving computers that contain a stunning array of information that can chart a detailed picture of our private lives," Wessler said.

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Originally published on June 19 at 5:00 a.m. PT.

Updated at 8:07 a.m. PT: To include details from arguments from the Georgia Supreme Court on Wednesday.