No Warrant Needed for Cell Phone Tower Location Data

Do police need a warrant to access cell phone tower location data?

Last year, the 11th Circuit Court of Appeals appeared to have triggered a circuit split on this question. It initially decided that a warrant supported by probable cause was required to access cell phone tower location data. At least two other circuits had decided that a warrant was not required. But an en banc panel of the 11th Circuit reversed that opinion and held that a warrant is not required. Police only have to show "'specific and articulable facts showing that there are reasonable grounds to believe' that the records sought 'are relevant and material to an ongoing criminal investigation.'"

Cell phone tower data was used in the prosecution's case against Adnan Syed who was convicted of the 1999 murder of his girlfriend near Baltimore and documented by the Serial podcast. The 11th Circuit noted in its opinion that location data that comes through cell phone towers is not unambiguous. For example, the towers have different areas of influence. The towers can sometimes indicate if the subject cell phone was north, south, east, or west of the tower. But that information is not reliable.

Regardless of the reliability of cell phone tower data, a person's location can be very private. The 11th Circuit's decision sought to balance the individual's privacy concerns against law enforcement needs. It held that consumers should address their concerns to cell phone service providers or the legislature. "'[T]he recourse for these desires is in the market or the political process; in demanding that service providers do away with such records (or anonymize them) or in lobbying elected representatives to enact statutory protections.'"

The 11th Circuit had been the first to hold that law enforcement requests for location data must be supported by probable cause. The en banc reversal makes it less likely that the United States Supreme Court will decide the issue.

State v. Davis
http://online.wsj.com/public/resources/documents/2015_0505_11thdavis.pdf