Police blotter: Judge lets Feds track cell phones

Federal judge approves a Patriot Act request to monitor the location of cell phones. Other courts have denied similar requests.

Declan McCullagh Former Senior Writer
Declan McCullagh is the chief political correspondent for CNET. You can e-mail him or follow him on Twitter as declanm. Declan previously was a reporter for Time and the Washington bureau chief for Wired and wrote the Taking Liberties section and Other People's Money column for CBS News' Web site.
Declan McCullagh
3 min read
"Police blotter" is a weekly report on the intersection of technology and the law.

What: Invoking the Patriot Act, the Justice Department asked to eavesdrop on the location of a cell phone user without providing evidence that criminal activity was taking place.

When: U.S. Magistrate Judge Gabriel Gorenstein, in the Southern District of New York, ruled on Dec. 20 (click here for PDF).

Outcome: Cell phone tracking permitted.

Summary: Federal police may monitor the locations of Americans by constantly tracking their cell phone signals without providing evidence of criminal activity, a magistrate judge has ruled.

In a surprise ruling that differed from recent decisions by three other judges, Gorenstein said his reading of federal wiretapping law and the Patriot Act permitted police to obtain location-tracking orders without any evidence of wrongdoing.

Gorenstein also said that because the cell phone user's location is only available to police when a call is in progress, and because the location information is only a rough estimate, such tracking is permissible under the Fourth Amendment. That amendment, part of the Bill of Rights, prohibits "unreasonable" searches and monitoring.

The Justice Department has argued that it should be allowed to monitor Americans without having to show "probable cause"--that is, at least some evidence of criminal behavior. Instead, federal prosecutors say, all police need to claim is that the information obtained might in some way be "relevant" to a criminal investigation.

The Federal Defenders of New York filed a brief arguing that Americans should enjoy more privacy when being tracked in real-time through their cell phones. In a related letter (click here for PDF) sent earlier this month that the judge did not appear to consider, the Electronic Frontier Foundation argued that "only" a search warrant based on probable cause of wrongdoing satisfies the Fourth Amendment.

Gorenstein's decision this week was a surprise because other courts have rejected similar requests. That started with a decision, first reported by CNET News.com in a Sept. 2 installment of Police Blotter, from U.S. Magistrate Judge James Orenstein.

Excerpt from the court's opinion: "The only remaining question is whether the issuance of a court order for cell site information...is unconstitutional because it violates the Fourth Amendment's prohibition against unreasonable searches and seizures. (The public defenders' brief) discusses the issue in terms of whether the cell phone is a 'tracking device' and whether a warrant grounded in probable cause is necessary for the installation of such a device. But the data being sought by the government in this district is not what amicus believes it to be.

"The information does not provide a 'virtual map' of the user's location. The information does not pinpoint a user's location within a building. Instead, it only identifies a nearby cell tower and, for some carriers, a 120-degree face of that tower. These towers can be up to 10 or more miles apart in rural areas and may be up to a half-mile or more apart even in urban areas. Moreover, the data is provided only in the event the user happens to make or receive a telephone call. Thus, amicus' s reference to tracking devices and the cases considering this technology is not on point.

"The government does not seek to install the 'tracking device': the individual has chosen to carry a device and to permit transmission of its information to a third party, the carrier. As the Supreme Court has held in the context of telephone numbers captured by a pen register, the provision of information to a third party does not implicate the Fourth Amendment."