Please ensure Javascript is enabled for purposes of website accessibility

GPS tracking limited in serving arrest warrants

Magistrate Judge Susan K. Gauvey

The government cannot use the GPS in a suspect’s cell phone to find him and serve an arrest warrant unless it can show that he is a fugitive, a federal magistrate in Baltimore has held.

The 139-page opinion by Magistrate Judge Susan K. Gauvey comes more than a year after investigators applied for a warrant in U.S. District Court to use the suspect’s cell phone against him.

“In so doing, the government asks to use location data in a new way — not to collect evidence of a crime, but solely to locate a charged defendant,” Gauvey wrote, noting that the government had not submitted any evidence that the suspect had attempted to flee.

Under the circumstances, she wrote, allowing investigators to track the suspect’s location using the GPS chip in his cell phone would violate his Fourth Amendment right against unreasonable searches and seizures. Gauvey also said cell phone owners were entitled to a reasonable expectation of privacy, which would be inconsistent with tracking them wherever they went.

If such searches are to be allowed, she wrote, the decision should come from the legislature or an appellate court.

“Some might say that this is an appropriate use of a new technology in the service of more efficient and effective law enforcement. Others might say it is an unnecessary use of a new technology in a society already subjected to pervasive surveillance,” Gauvey wrote. “The Court understands the tension. Regardless of individual views, the law does not currently sanction the requested acquisition of location data in these circumstances.”

Mooted by arrest

The owner of the cell phone was not named in opinion, and the court redacted his name and phone number.

The initial application was made in June 2010. According to court records, the owner of the phone was arrested a few days after the application to track the cell phone was filed.

Gauvey’s opinion said that, given the uniqueness of the request and the likelihood it will come up again, the opinion was still necessary.

Not so, U.S. Attorney Rod J. Rosenstein said in a statement.

“[T]he issue was already moot when the judge ordered lawyers to file briefs and argue at a hearing more than one year ago,” the statement said.

Rosenstein said he still supported the initial application and would push for the right to use the technology again in future cases.

“The Justice Department cannot appeal Magistrate Judge Gauvey’s advisory opinion because it is moot. It also is nonbinding. If the issue arises again and we need the order to enforce a judicial arrest warrant, we will have the opportunity to bring it to another judge and appeal if necessary.”

The decision was praised by the Electronic Frontier Foundation, a digital rights group based in San Francisco. The group said the decision was a win for personal privacy.

“This opinion is part of a growing consensus that our Fourth Amendment rights protect us from having our location revealed by the GPS chips in our cell phones,” said Kevin Bankston, a senior staff attorney with the EFF. “It says that we have a reasonable expectation to privacy that is not limited, just because the phone company has the ability to locate us.”

Enhanced 9-1-1

Rosenstein also indicated that cell phone owners realize the device has the ability to pinpoint their location.

“I voluntarily carry a BlackBerry,” his statement said. “That means Sprint knows where my phone is at all times.”

The technology to track the GPS chips is tied in with the Federal Communications Commission’s wireless Enhanced 9-1-1 rules. With so many people using cell phones as their primary means of communication, the E-9-1-1 rules were created to allow emergency personnel to pinpoint and route a call to the nearest agency. Depending on the technology, GPS-enabled phones can be tracked to an area ranging from at least 50 yards to 300 yards.

A GPS chip is included in most phones manufactured in recent years. The chip receives the signals from an orbiting constellation of GPS satellites and takes that information to calculate the three-dimensional position of the handset.

According to the opinion, the consensus was that given the state of technology now, law enforcement could have pinpointed the suspect’s location to within 10 yards. The government also wanted to “ping” his cell phone to get the cell site location. (Pinging allows the phone company to send a signal, unbeknownst to the cell phone owner, that allows the phone company to determine what the nearest cell tower is and use that information to triangulate a location.)

Bankston said issues of privacy surrounding cell phone tracking would continue to crop up nationwide as the technology advanced to the point law enforcement would try to utilize it — and the precedents concerning those efforts were few and far between.

“We are all carrying precise tracking devices with us everywhere we go,” Bankston said. “These are devices that can be used to track us under unclear legal authority.”

He said applying the investigators’ logic to other situations supports the court’s decision.

“It’s analogous to the government having carte blanche to search the home of anyone with an arrest warrant,” Bankston said. “Clearly, that would be too broad and it is too broad an application in this case as well.”