When the Supreme Court hears Carpenter v. United States this November, the justices will determine whether law enforcement can seize and search an individual's cell phone location data — revealing virtually all of the person's movements — without a search warrant.
While privacy advocates could get their day in Court, their data will stick around long after the case is decided. Here is a look at what happens to the cell phone data transmitted within a two mile radius of the United States Supreme Court:
[Image: Map of cell phone towers within two square miles of Supreme Court]
Within two miles of the Supreme Court, cell phone signals are intercepted by any number of the 973 antenna, connecting cell phones to 136 cell towers (above) every 7-9 minutes on average. It can, however, attempt to connect as frequently as every 7 seconds.
After connecting with the tower, these data exchanges allow cell phone service providers to store data for up to 5 years. A single request from a law enforcement or other government agency official to the cell phone service provider can be used to collect days, or even months, of data.
Each year, service providers receive tens of thousands of requests for precise GPS coordinates of the device or call detail records. In 2016 alone, 70,000 demands for location data received by AT&T. Notably, less than one third (24,711) of these demands involved a search warrant or probable cause court order.
Under the third-party doctrine, privacy protections do not apply to cell phone data because the user "voluntarily conveyed" the information by deciding it was necessary to own a cell phone and to turn the power on. (See Graham). In Carpenter, police were able to obtain 127 days' worth of data -- revealing about 12,898 separate points of location data -- without the finding of "probable cause" required to issue a search warrant.
In our analyses of Carpenter v. United States, we argue that the third-party doctrine is at odds with the protections found in the Fourth Amendment, and that to preserve the right to privacy we must return to the text of the Constitution.
When dealing with questions of privacy in the digital age, the Constitution already gives us a clear answer: A warrant will always do.