Supreme Court rules police need a warrant to access a suspect's cellphone location data

The Supreme Court ruled 5-4 today that police cannot freely access people's cellphone location data, regardless if they are suspected for a crime.

Police have always needed court-approved warrants before searching people's phones (due to the search and seizure protections under the Fourth Amendment), but they routinely breeched that protocol by accessing data from wireless carriers without a court's permission.

Phone privacy rights — from wiretaps to location data — have long been debated in the courts, so today's ruling is a symbolic win for privacy advocates and somewhat of an upset for law enforcement.

Although the narrow ruling restricts what information law enforcement may use, the precise wording of today's decision still provided wiggle room for them because it only stipulates that a warrant is generally required.

SEE ALSO: ACLU: Tracking Your Cellphone Location Should Require a Warrant

"We decline to grant the state unrestricted access to a wireless carrier's database of physical location information," wrote Supreme Court leader John Roberts in the decision.

"In light of the deeply revealing nature of (cell site location information), its depth, breadth, and comprehensive reach, and the inescapable and automatic nature of its collection, the fact that such information is gathered by a third party does not make it any less deserving of Fourth Amendment protection."

Timothy Carpenter, the winner in today's years-long case, was sentenced to more than 100 years for an armed robbery based on the information police gathered from his phone without a warrant. A jury found him guilty after they determined his involvement in the crime by identifying which cell towers Carpenter's phone pinged.

The police didn't have enough evidence to convict Carpenter before obtaining the warrants, since he did not commit the armed robbery — Carpenter coordinated.

He, therefore, worked with the ACLU to say that the information gathering breeched his privacy and took it all the way to the Supreme Court last year.

But he isn't the first person to bring this concern to the judicial system. It goes all the way back to the 1970s, when Smith v. Maryland appeared in the country's High Court.

That case swung the other way, however, where the justices ruled that people have no expectation of privacy when their data is already given to a third party. And how times have changed since then — think of it like how we give our information to Facebook and how Cambridge Analytica then accessed that data.

The more conservative justices who voted against restricting what information police could access feared that it impeded investigations and extended the reasonable expectation of privacy too far.

"I share the Court's concern about the effect of new technology on personal privacy, but I fear that today's decision will do more harm than good," wrote Justice Samuel Alito in the decision document.

"The Court’s reasoning fractures two fundamental pillars of Fourth Amendment law, and in doing so, it guarantees a blizzard of litigation while threatening many legitimate and valuable investigative practices upon which law enforcement has rightfully come to rely."

Other cellphone privacy lawsuits include United States v. Jones in 2005, Commonwealth v. Connolly in 2017, and State v. Earls in 1982, which all ruled that police need a court-approved warrant before putting location trackers on people and Riley v. California in 2014, which said police needed a warrant before searching the contents of someone's phone.

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