Fresh concerns about digital privacy and security are budding in Washington amid revelations of potential surveillance activity in the D.C. region in the USA

Officials with the Department of Homeland Security (DHS) recently disclosed signs of sophisticated technology, known colloquially as “Stingrays,” near sensitive facilities including the White House.

The devices, International Mobile Subscriber Identity (IMSI) catchers, exploit cell towers to potentially intercept cellphone communications. The technology has historically been used by law enforcement officials to track suspects, but the new revelations have bolstered fears that foreign intelligence agencies could be using them to spy on U.S. officials.

Sen. Ron Wyden (D-Ore.) is demanding action from the Federal Communications Commission (FCC) and private phone companies to better protect Americans from being spied on or tracked.

In an interview with The Hill Tuesday, Wyden accused FCC Chairman Ajit Pai of “stonewalling” his pleas for action.

“Mr. Pai and the FCC are dragging their feet here,” Wyden said. “They are stonewalling. They are ducking. They are trying to conjure up any possible reason to sit it out.”

Pai so far has declined to investigate Stingrays further, but says his agency is open to digging into the matter down the road.

The controversial technology works by masquerading as legitimate cellphone towers, tricking mobile devices to locking onto them, enabling would-be spies to track individuals’ locations or to intercept communications.

Often, the devices work in tandem with a vulnerability in Signaling System Seven (SS7), the global telecommunications standard that connects phone networks, allowing them to swap information necessary to complete calls and send text messages.

“We have a system that was designed in 1975 to work, and security was an afterthought,” said Christopher Meserole, a technology expert at the Brookings Institution.

“The security flaws have been known for a long time,” he said. “They’ve never really been addressed because the underlying technology is so useful.” 

Privacy and civil liberties advocates have long argued that law enforcement faces few checks in using the devices, raising broader concerns about privacy intrusions.

“This is not a new problem,” said Drew Mitnick, policy counsel at Access Now. “We see catchers used pretty broadly by state, local and federal law enforcement. There hasn’t yet been the success in establishing the appropriate limits on the use of these devices.”

Suspicions that foreign intelligence agencies use the device to spy in Washington have circulated for some time.

But it wasn’t until April, in a letter to Wyden, that Homeland Security acknowledged “anomalous activity” likely related to IMSI catchers in the Washington region, a revelation that quickly triggered concerns on Capitol Hill.

“I would think if in fact there are foreign intelligence agencies using this technology, that should be a high priority for us in terms of determining that,” Rep. Adam Kinzinger (R-Ill.) said at a House Energy and Commerce Committee hearing last month, calling the activity a “big concern.” He suggested Homeland Security should share more information with industry in order for companies to help the government locate the devices.

Last week, Wyden released a subsequent letter from Christopher Krebs, a top official at Homeland Security’s National Protection and Programs Directorate, revealing that the department detected the suspected surveillance activity “in proximity to potentially sensitive facilities like the White House” last year.

Krebs said the department had not attributed the activity to “specific entities,” and he added that a subsequent investigation by law enforcement and counterintelligence agencies revealed that some of the signals were emanating from “legitimate cell towers.”

The FBI declined to comment on Tuesday.

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