The top Democrat and Republican on the Senate Judiciary Committee said on Wednesday that they want answers from the Obama administration about cell phone tower simulators used by law enforcement to intercept cellphone data.
The bipartisan letter was sent to the departments of Justice and Homeland Security by Sen. Patrick Leahy, D-Vt., and Sen. Chuck Grassley, R-Iowa. It questions law enforcement's use of a tool referred to as a "dirtbox," pointing to a November article by The Wall Street Journal describing the technology.
The device is typically used from an airplane and mimics a cellphone tower, tricking cellphones into identifying the owner's information and allowing law enforcement to gather data from tens of thousands of cellphones in a single go without having to ask service providers, reported The Associated Press.
While law enforcement maintain they only use the device on suspected criminals, personal data of innocent civilians is inevitably captured as well, and the senators demand an explanation for how the privacy of those innocent citizens is protected.
"The Judiciary Committee needs a broader understanding of the full range of law enforcement agencies that use this technology, the policies in place to protect the privacy interests of those whose information might be collected using these devices, and the legal process that DOJ and DHS entities seek prior to using them," the senators wrote.
A Justice Department official told the WSJ that agencies comply with federal law and seek court approval before targeting suspects.
In the letter, the senators mention that an FBI policy change now requires the agency to obtain a search warrant prior to deploying the interceptor, noting however that there are "a number of potentially broad exemptions," in cases that threaten public safety or involve a fugitive.
The senators listed a number of questions in the letter, including ones asking how often the technology has been used and how often law enforcement first obtain a search warrant, reported the AP.
A Justice Department spokeswoman told the AP that it was reviewing the letter.
