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Carpenter v. United States - Oral Argument Before the Supreme Court on Cell Phone Tracking

This week a transcript (and audio) was posted of an oral argument before the Supreme Court in Carpenter v. United States, No. 16-402 (U.S.), a case in which the court is to decide whether the warrantless seizure of cell phone data to track the location of a defendant violates the Fourth Amendment. The decision of the Sixth Circuit was that 'cell-site data' did not constitute the content of communications which the Fourth Amendment protects. The data was collected from a service provider, not Carpenter, and so it did not constitute a search.

Nathan F. Wessler presented the argument for the petitioner, and Michael R. Dreeben spoke for the respondent. The petitioner argued that the collection of 127 days of data on Carpenter's location was a search.

Petitioner proposed a 24 hour period as limit on how much information the government could collect on a particular individuals' whereabouts. Justice Sotomayor questioned whether or not police could get a tower dump of a cell site in order to see who was in the area at the time of a robbery - collecting all call data from multiple users at moment in time. The petitioner thought that would be acceptable. (H'rg Tr. at 8).

Justice Sotomayor suggested that the Court's prior decision preventing the government from touching someone's bag, even though it was exposed in public, was analogous to this case because someone neither had the expectation that their bag would be touched, nor the expectation that their location could be tracked over 127 days even though they might believe their location at any one moment could be ascertained. (Id. at 23-24) Wessler noted that a survey indicated that most Americans don't believe that service providers can access the information on their phones, much less be retained by the providers. (Id. at 17).

The facts of this particular case may effect the decision the court reaches. The MetroPCS contract for the petitioner's cell phone account stated that the customer's information could be disclosed to the government if a request was made pursuant to a court order. (iI. 16-17). The cell phone records at issue in this case date from 2010 - 2011. Wessler made much of the fact that current smart phones make possible the collection of far more extensive location data:

" . . . in the intervening seven years, the data has become markedly more precise. The proliferation of small cells which can have a broadcast radius as small as 10 meters, just skyrocketing amount of data usage by normal smartphone users means that even the large traditional cell towers are much closer together in urban and dense suburban areas, so the distance between them is less, so they are significantly -- the location information is more precise." (Id. at 29-30)

Justice Gorsuch brought up the E911 program, a government regulation, that requires service providers to track cell phone locations in real time - but does not require them to retain the information. (Id. at 30).

Speaking for the respondent, Dreeben made a distinction between GPS information obtained from a phone and the acquisition of cell site information received from a business. He said that, "The expectations of privacy about the contents of one-to-one communication or a many-to-many communication are quite different." (Id. at 44) He distinguished between routing information and content information. Dreeben further thought there was a distinction between getting information from an individual and requesting that a business serve as a witness for the government - there was no direct government searching activity in Carpenter (Id. at 68).

Justice Kagan wondered whether or not there was a difference between this case and the decision in United States v. Jones, 132 S.Ct. 945 (2012), in which it was ruled that attaching a GPS device to a car was a search under the Fourth Amendment. Justice Kagan found the cases similar in that they both concerned a new technology that allowed for 24/7 tracking and changed people's expectations of how they could be monitored. (Id. at 47).

Under further questioning by Justice Kagan, Dreeben conceded that a request to a cell phone company for lifetime information for a particular customer would be highly questionable under the Constitution. (Id. at 73-75).

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