The Supreme Court ruled Friday that authorities generally need a search warrant before they can obtain broad access to data that shows the location of cellphone users, a decision that sets privacy boundaries in the digital age.
The court, in a 5-4 opinion by Chief Justice John Roberts, cited the Fourth Amendment’s guarantee to be free from unreasonable government searches.

And

We decline to grant the state unrestricted access to a wireless carrier’s database of physical location information[.]

Yewbetcha.