The Washington Post reports on a surveillance system to gather data from cellphones and other devices that is being used by federal investigators in California; the surveillance tool is raising privacy and civil liberty questions:
Federal investigators in Northern California routinely used a sophisticated surveillance system to scoop up data from cellphones and other wireless devices in an effort to track criminal suspects — but failed to detail the practice to judges authorizing the probes.
The practice was disclosed Wednesday in documents obtained under the Freedom of Information Act by the American Civil Liberties Union of Northern California — in a glimpse into a technology that federal agents rarely discuss publicly.
The investigations used a device known as a StingRay, which simulates a cellphone tower and enables agents to collect the serial numbers of individual cellphones and then locate them. Although law enforcement officials can employ StingRays and similar devices to locate suspects, privacy groups and some judges have raised concerns that the technology is so invasive — in some cases effectively penetrating the walls of homes — that its use should require a warrant.
The issues, judges and activists say, are twofold: whether federal agents are informing courts when seeking permission to monitor suspects, and whether they are providing enough evidence to justify the use of a tool that sweeps up data not only from a suspect’s wireless device but also from those of bystanders in the vicinity.
In Northern California, according to the newly disclosed documents, judges expressed concerns about the invasive nature of the technology. […]
The Justice Department has generally maintained that a warrant based on probable cause is not needed to use a “cell-site simulator” because the government is not employing them to intercept conversations, former officials said. But some judges around the country have disagreed and have insisted investigators first obtain a warrant. […]
One of the problems is there is “scant law” addressing the issue of cell-site simulators, said Brian L. Owsley, a federal magistrate judge in the Southern District of Texas, who in June wrote a rare public ruling on the issue. He denied an application to use a StingRay, in large part because he felt the investigating agent failed to explain the technology or how it would be used to gather the target’s cellphone number.
Moreover, the government did not explain what it would do with the numbers and other data “concerning seemingly innocent cell phone users” that were also picked up.