HOUSTON—Police and federal agents in Houston are increasingly using cell phone data to track citizens who have possible connections to crime. But at least one federal magistrate is starting to question the practice.
First, here’s how it works: Police can get your cell phone company to turn over records kept on every call you make. The records reveal the location of the cell towers that receive your phone’s signal. Your location can then be estimated within about a quarter mile.
"If they can locate the cell phone transmission point, the theory is perhaps they can put you at the scene of the crime," said Patrick McCann, criminal defense attorney.
Police can also get data from the phone company so they can follow you in real-time, tracking the tiny GPS device in your phone.
"I think it’s something that’s definitely on the increase," said Caroline Dozier, and Assistant Harris County District Attorney.
And it’s something law enforcement says can definitely work.
One notorious Houston case was an arson fire in 2004 at the El Festival Ballroom in north Houston. The blaze killed a firefighter, but the suspects were long gone. So police tracked their cell phones.
Records from the phone company showed calls were made near a motel in Dallas. Police moved in and caught the arsonists.
"They’d probably still be on the run because they were very good at forging identification cards and driver’s licenses," said Dozier, who handled the case.
To track a phone, police first must get permission from a judge or magistrate. It’s something happening routinely in Houston, both at state district court and at the federal level.
"It’s a daily thing. We get one or two a day," said United States Magistrate Judge Stephen Smith at the federal courthouse in downtown Houston.
Exact numbers are hard to come by, because the court orders for the cell phone data are requested and granted in secret, behind closed doors.
"These are all sealed. They stay sealed," said Federal Magistrate Stephen Smith. "It’s a concern. If they search your house, you know it. With this, you never know it happened."
That’s one thing that troubles Judge Smith, who said he wants to bring attention to the issue by speaking to the media—a rarity for federal judges.
The big concern is privacy. The Constitution protects it, but technology now available to the police can threaten it. And Judge Smith said that the existing laws, written before the explosion of cell phones, don’t give enough guidance to judges trying to decide if police requests are Constitutional.
The fear is that police might abuse the power to find out where we’ve been, all the while without the cell phone user ever knowing.
"If the police are left to sit there and say trust us, we’re not misusing this information, guaranteed within one millisecond of them saying that someone is misusing that information," said Patrick McCann, a criminal defense attorney in Houston.
As an example, he pointed to the case of a Harris County deputy accused last month of selling confidential information from a national crime database.
Could the same happen to your cell phone information?
"We require that a district court judge sign off on all cell phone court orders," said Dozier.
She said judges do a good job of making sure police are going after people who are true suspects and are not just doing "fishing expeditions" just to see what they can find.
