U.S. lawmakers on Thursday demanded answers about the Baltimore Police Department's widespread use of a controversial cellphone surveillance device and blasted the FBI for seeking to quash the public release of information about the program.
Maryland Rep. C.A. Dutch Ruppersberger said he has asked the FBI for "greater clarification" about how the device is deployed, while Sen. Chuck Grassley, an Iowa Republican and chairman of the Senate Judiciary Committee, said the FBI appeared "blind to the benefits of transparency."
The legislative response follows revelations that Baltimore police have used what's commonly known as a "stingray" 4,300 times since 2007 — a number that dwarfs known usage by other departments — but have been bound by a nondisclosure agreement with the FBI that forbids them from telling the public or even judges and lawmakers about the device.
"As a former investigative prosecutor who worked closely with the FBI, I understand technology can be very useful to law enforcement to protect our citizens and apprehend the bad guys," Ruppersberger said. "But we have to be sure all tools are used lawfully and that they are used as transparently as possible."
The stingray acts as a police-controlled cellphone tower, forcing all phones in an area to connect to it, collecting their unique identifying information, and allowing police to pinpoint the target phone's location.
Developed as a tool to fight terrorism, the device has been acquired by dozens of law enforcement agencies across the country and, at least in Baltimore, used for routine investigations such as locating stolen cellphones.
Rep. Andy Harris, a Maryland Republican, said he believes the issue should be part of a larger discussion "about the use of new data collection techniques by law enforcement and the fear that the data gathered by a device such as the stingray will be retained by the government."
The FBI declined to comment Thursday about the new disclosures but pointed to past statements in which the agency has defended the secrecy surrounding the stingray technology. They have argued that disclosing more information could undermine the device's effectiveness and potentially enable criminals to circumvent it.
Police say they obtain court orders before using the cell site simulator, but the scope of the technology's use has been deliberately concealed because of nondisclosure agreements, which include instructions from the FBI to drop criminal prosecutions should questions about the technology arise.
Privacy advocates question the level of secrecy that accompanies the stingray and whether there is proper oversight. They also contend the nondisclosure agreements violate the Fourth Amendment.
Before this week, Baltimore police had declined to discuss their use of the device, with a detective in one instance nearly held in contempt for invoking the nondisclosure agreement in court. Then on Wednesday, a detective with the Police Department's phone tracking unit testified in court about police using a cell site simulator thousands of times.
On Thursday, a commander said that it is an important tool for fighting crime and is deployed responsibly.
"We will use every resource available to reduce violent crime and arrest people responsible for those violent crimes. Our citizens expect and demand nothing less," said Capt. Eric Kowalcyzk, the agency's chief spokesman.
Kowalcyzk said police use the device "in compliance with state law, under judicial review, and in conjunction with our state's attorney partners."
He said the device does not allow police to record calls or see texts, emails or photos, and the information that is collected is not stored. He said police sometimes use the device without a court order in exigent circumstances but then obtain an order after the fact in such cases.
State's Attorney Marilyn Mosby did not respond to requests for comment.
Joshua Insley, a Baltimore defense attorney who has been fighting for disclosure of stingray use, called the police statement "nothing but misdirection."
"They want to make the discussion about whether it is a good crime-fighting tool or not. It obviously is," Insley said. "The problem with [Wednesday's] revelations are about the manner in which it is operated."
Baltimore County police on Thursday also acknowledged for the first time that they have had a stingray since 2010, using it more than 600 times. Baltimore County State's Attorney Scott Shellenberger said it has helped police locate phones, from which he said investigators then extract "powerful" information to win convictions. He said the information is obtained "lawfully."
In addition to Baltimore City and Baltimore County, Anne Arundel, Prince George's and Montgomery counties are among the Maryland police agencies that have obtained cell site simulators over the years, according to the American Civil Liberties Union.
Police obtain a court order called a "pen register" in order to get authorization to use the stingray. Within the text of those orders, police say they plan to use real-time GPS tracking of cellphones.
Critics say the pen register statute is generally understood to refer to less intrusive cellphone surveillance, and judges have not been aware of what they were authorizing because of the FBI's prohibition on disclosure.
Retired Maryland Chief Judge Robert M. Bell said he was troubled that information has been withheld from judges.
"You certainly have to be concerned about the integrity of the process when it comes to authorizing surveillance," Bell said. "To the extent that information is withheld, that should concern judges."
Hanni Fakhoury, an attorney with the Electronic Frontier Foundation, said cases should be reopened to examine whether police were untruthful in affidavits in requests for court orders to use the devices.
"All of this is extraordinarily insane, and so improper on so many levels," he said. "This thing is designed to keep judges in the dark."
Federal officials have said that discussing the technology could endanger police officers and undercut terrorism investigations. When a Maryland State Police commander was asked about it at a legislative hearing last spring, he cited "homeland security" as a reason for being unable to provide information.
The Baltimore agreement was signed in 2011 by then-Police Commissioner Frederick H. Bealefeld III and then-State's Attorney Gregg Bernstein. Bernstein declined to comment Thursday, and Bealefeld did not return calls seeking comment.
Grassley has been pressing the Obama administration for information on the use of cell site simulators. He told The Baltimore Sun that he believes there should be reporting on how often the technology is used, under which legal authorities, and what independent audit controls are in place to prevent abuse.
"No one wants the bad guys to obtain information that would allow them to evade law enforcement, but basic transparency can assure the public that the technology is not being abused," Grassley said.
Baltimore Sun reporters John Fritze and Alison Knezevich contributed to this article.