Ventura Criminal Justice Attorney
Can Police Track Your Cell Phone Without a Warrant?
The digital age has provided a host of new issues with law enforcement, many of which deal with the intersection of privacy rights and criminal law. Law enforcement officials have been straining to retain the ability to get as much information as possible from our digital selves without having to go the historical (and constitutional) route of waiting until they have probable cause of a crime and obtaining a search warrant. A recent Supreme Court case involving such a search dealt a substantial victory for advocates of the rights of the accused. In short, police cannot track cell phone location data without a warrant. Read on for more about the Supreme Court’s decision, and contact an experienced California criminal defense attorney with any questions.
Police Use Cell Phone Location Information Obtained Without a Warrant as Evidence
Cell phones operate by continually connecting to radio antennas known as “cell sites.” Each time a phone connects to a new cell site, it creates a time-stamped record known as “cell site location information” (CSLI). Wireless companies retain this information for business purposes. In Carpenter v. United States, the FBI and prosecutors sought to use CSLI to establish the whereabouts of criminal defendants around the time of several alleged robberies.
As part of their investigation, the FBI identified the cell phone numbers of the defendants. The government prosecutors then sought and received court orders to obtain the phone records of the defendants. The orders were granted under a federal law which allows police to track data, like cellphone information, with a court order based on facts granting “reasonable grounds to believe” the records are “relevant and material to an ongoing investigation.” This is a lower standard than the probable cause necessary to obtain a search warrant, which requires a reasonable belief that the evidence will lead to the confirmation of the commission of a crime.
The cell companies provided the CSLI. For the named defendant-petitioner in Carpenter, the government was able to obtain almost 13,000 location points detailing his movements over 127 days. Carpenter sought to suppress use of the data at trial, arguing that the government had seized those records without warrants supported by probable cause, and in doing so had violated his Fourth Amendment rights. The trial court rejected the motion, and Carpenter was convicted, in part based on the location data showing that he was near four of the robberies when they were committed. The appellate court affirmed the conviction, holding that Carpenter had no reasonable expectation of privacy with regard to the location data because the data was already being shared with wireless carriers. If you are doing something in public or providing information publicly, without an expectation of privacy, then law enforcement agents do not have to get a warrant before obtaining that information or observing your public behavior.
Supreme Court Says the Government Needs a Warrant to Obtain Location Data
The Supreme Court disagreed with the lower courts. The Court found that location data is a new phenomenon, but more closely resembles GPS tracking, which a previous case decided requires a warrant. Even though the information is shared with the wireless carrier, people have a right to expect that their every waking movements are not being tracked, catalogued, and shared with police. Cell phones are, at this point, an essential feature of daily life, and our “sharing” of location data with the wireless companies is necessary for them to function. Moreover, cell phones share data automatically; people do not actively click “share location data” every time they enter a new cell site. For these reasons, the Court found that people do have a reasonable expectation of privacy with regard to cell phone location information, and if the government wishes to obtain that information for use in a criminal proceeding, it must obtain a search warrant by establishing probable cause.