Original Post 2/11/10: Oral Arguments in Cell Site Locator Case Moved to Friday
The long awaited oral arguments in the Third Circuit over whether the Government must make a probable cause showing to get your cell site locator information has been moved to Friday at 9:30 a.m.
This case is a big deal. The Third Circuit is the first federal appeals court to decide the issue. I have motions to suppress pending in several cases that will be affected by the outcome.
The core of the argument is that the disclosure of cell site information turns a mobile telephone into a "tracking device" and disclosure may not be authorized without a showing of probable cause. The Government has been seeking (and in many cases courts have granted) the information based on the lesser standard of simply alleging the information will be relevant and helpful to an investigation. Some magistrate judges around the country rejected the requests (example here), and it's now before the Third Circuit.
Cell site data provides the location of the cell phone tower supplying service to a cell phone during a telephone call. It can be obtained from the cell phone service provider within a few seconds of the call.
Geo-location information provides the location of a cell phone within several hundred meters. In providing the information to the Government, cell phone companies are informing it of the specific location of a phone at a particular time.
The case is In the Matter of the Application of the United States of America for an Order Directing a Provider of Electronic Communication Service to Disclose Records to the Government and the District Court opinion is at 534 F. Supp. 2d 585 (W.D. PA. 2008.) You can read it here. The District Court affirmed the Magistrate's order finding probable cause was necessary. The Amicus brief of EFF and the ACLU and other groups is here.
In some cases, the Government asks for cell site location data not just of the phone it is investigating, but for all numbers dialed to and from the phone. That could be anyone.
For updates tomorrow, head over to EFF.org.