GPS Act Aims To Stop Warrantless Smartphone Tracking Done With Cell-Site Simulators

A StingRay device, made by the Harris Corporation

Senators Ron Wyden (D-Oregon), Rep. Jason Chaffetz (R-Utah), and Rep. John Conyers, Jr. (D-Michigan), introduced the Geolocation Privacy and Surveillance (GPS) Act to stop law enforcement from using cell-site simulators to track anyone they want without first obtaining a warrant.

Cell-Site Simulators Increasing In Popularity

Cell-site simulators, sometimes called “IMSI catchers,” or “Stingrays,” (the name of one of the cell-site simulator brands), are tools that masquerade as wireless cell towers on a target’s device. The user of a cell-site simulator can force phones within a relatively limited area to switch from the official cell towers they use to the simulated tower. This allows the user to intercept phone calls and messages received or transmitted by the target, as well as track the location of the target.

Cell-site simulators have been in use for more than a decade by U.S. law enforcement, in limited capacity. However, as their popularity with law enforcement grew, civil liberties groups became worried about how they're used. As it was later discovered, the devices are often used without a warrant, and their use tends to be kept secret even from judges.

At times, the FBI has trained police officers to not testify about the use of cell-site simulators. Prosecutors have also been trained to drop the cases and let the alleged criminals free, if continuing the case would put the secrecy of cell-site simulators in jeopardy. Other times, legal tricks such as claiming non-disclosure agreements with the companies from which the devices were purchased were used to keep their use hidden from judges.

The FBI has claimed that revealing the use of these tools would put operations in danger. However, the fact that cell-simulators exist is no secret, and the companies making them often participate at public tradeshows, where they try to sell them to law enforcement.

The issue with cell-site simulators being used without a warrant is not just that the rights of the intended targets are infringed upon, but also those of everyone in the area. A cell-site simulator will work against everyone in the device’s range.

“Outdated laws shouldn’t be an excuse for open season on tracking Americans, and owning a smartphone or fitness tracker shouldn’t give the government a blank check to track your movements,” said Wyden. “Law-enforcement should be able to use GPS data, but they need to get a warrant. This bill sets out clear rules to make sure our laws keep up with the times,” he added.

Congressman Jason Chaffetz, who was one of the GPS Act’s co-sponsors, also commented on the importance of the bill.

“Congress has an obligation to act quickly to protect Americans from violations of their privacy made possible by emerging technologies,” said Chaffetz.“As we welcome innovative technologies that help fight crime, we must be mindful of the potential for abuse. This bill will build a framework governing the use of geolocation and cell site simulator technologies,” he noted.

Courts Have Been Split On The Issue

The Supreme Court also ruled in 2012’s U.S. vs. Jones case that attaching a GPS tracking device to someone’s car without a warrant is a clear violation (the decision was unanimous) of that person’s rights.

One would think that this means any sort of GPS or geolocation tracking by law enforcement would be similarly unconstitutional, as the main difference lies in the technologies being used to do the tracking. However, the lower courts have been relatively split on this so far. Some have allowed warrantless cell-site simulator tracking to be done, whereas others have called it unconstitutional.

This has prompted civil liberties groups to ask for a new law that would make it clear that warrantless tracking of people’s location or the interception of their communications is illegal.

Neema Singh Guliani, legislative counsel at the American Civil Liberties Union, said: “In today’s world, most Americans use cell phones or other electronic devices that are capable of tracking their every move, including visits to a mosque, doctor’s office, domestic violence shelter, or political rally. This information that the government should not be able to get without a warrant – yet law enforcement routinely fails to meet this standard. Congress should swiftly pass the GPS Act to protect this sensitive information.”

The GPS Act seems to have some bipartisan support as it’s being introduced, but it will remain to be seen what the chances for passage are in the coming months. Some of the staunch surveillance defenders seem to have changed their minds about the potential for abuse of warrantless surveillance recently. Therefore, similar bills could have better success than expected, if they are to be believed and if they actually intend to curb surveillance powers that are used without judicial warrants.

Lucian Armasu
Lucian Armasu is a Contributing Writer for Tom's Hardware US. He covers software news and the issues surrounding privacy and security.
  • Daekar3
    The government absolutely should pass this. The out of control alphabet soup agencies have been abusing their power long enough. Our collective values dictate a policy of freedom, transparency, and respect for personal rights, not oppression, secrecy, and mass surveillance.
  • shrapnel_indie
    While I have my doubts about how this will actually curtail the practice (They'll find a judge who will give them a "yes" practically every time they ask, or go ahead and do it anyway under guises of "patriot act" use. Unfortunately when Govt is in bed with law/enforcement and/or the judicial system.... things will get ignored, or instructed to be kept private usually in favor of some political group or super-group (especially if "above the law") protecting their own and/or their power.

    I do believe these things are too large a net and susceptible to misuse/abuse. Plus, who knows what criminals may have obtained for illicit theft of data. (End to end encryption IS a must... but unfortunately is and will never be, 100% secure against the right tools and enough time.)
  • Stubbies
    Yeah LE has already proven with civil asset forfeiture that if you give them a chance to abuse something they will do so and vehemently fight to keep that ability to abuse constitutional rights.
  • Wisecracker
    As typical, our Congress Critters have been asleep at the switch.

    Cell-site simulators drift-netting data/com streams along with GPS-tracking are an obvious violation of the 4th Amendment. Obscuring that obvious fact with NDAs and Federal G-Man 'training' on court testimony does not perfume the stench emanating from this lawlessness.

    BUT ..... rest assured, America. Congress will see that the perpetrators of these Constitutional violations receive retroactive immunity from prosecution for their crimes.
  • wsmith
    Am I to really believe that the telcos themselves couldn't easily prevent cell phones from connecting to anything but their own towers?