Future Tense

Judge OKs FBI Tracking Tool That Tricks Cellphones With Clandestine Signal

With a Stingray, even innocent bystanders’ mobile communications could be collected by law enforcement

Photo by NICOLAS ASFOURI/AFP/Getty Images

Back in March, the FBI was accused of hiding information from judges when seeking authorization for a clandestine cellphone tracking device called the “Stingray.” But now a judge has ruled that the feds’ use of the surveillance tool was lawful in a case that could have wider ramifications for law enforcement spy tactics.

The Stingray, sometimes described as an “IMSI catcher,” is a transceiver used by the FBI to locate suspects. As I have reported here previously, it sends out a signal that tricks phones within a targeted area into hopping onto a fake network. Civil liberties groups have challenged the lawfulness of the Stingray’s deployment, particularly because it intentionally gathers data from innocent bystanders’ phones and interferes with signals in a way that may be barred under a federal communications law. Documents released under the Freedom of Information Act have also appeared to show that the FBI knows its use of the device is in shaky legal territory. The technology has been used in some capacity by the feds for almost two decades, but only recently has it garnered attention, in part because of a court case in Arizona—U.S. v. Rigmaiden.

The ACLU had argued that evidence gleaned from a Stingray to track down Daniel Rigmaiden, who is accused of conspiracy, wire fraud, and identity theft, should be suppressed. The rights group alleged that when the FBI sought authorization to use the Stingray, it concealed information about the device. In an amicus brief, the ACLU wrote that “[b]y failing to apprise the magistrate that it intended to use a stingray, what the device is, and how it works, it prevented the judge from exercising his constitutional function of ensuring that warrants are not overly intrusive and all aspects of the search are supported by probable cause.”

But on Wednesday, Judge David Campbell dismissed the motion to suppress. Campbell concluded that the warrant was valid and that the suspect “did not have an expectation of privacy society is willing to accept as legitimate.” Campbell wrote that the suspect could not “credibly argue that he had a legitimate expectation of privacy” because he had allegedly rented his apartment and purchased his computer fraudulently using false identities. The judge also added that the use of the Stingray did not constitute a “severe intrusion” and ultimately held that “no Fourth Amendment violation occurred.”

The ACLU responded with dismay, stating that it believes the ruling “trivializes the intrusive nature of electronic searches and potentially opens the door to troubling government misuse of new technology.” Linda Lye, staff attorney at ACLU, wrote in a blog post that the group was particularly disgruntled that the judge appeared to dismiss the significance of the Stingray’s ability to scoop up data from innocent third parties, which the ACLU believes the feds do not fully disclose. Campbell’s approval of the Stingray in the Rigmaiden case, Lye wrote, sends the message that it is “alright to withhold information from courts about new technology, which means that the law will have an even harder time catching up.”

Incidentally, new FBI documents related to the Stingray were released by the Electronic Privacy Information Center on Wednesday. Four hundred pages of heavily redacted files, some marked “secret,” join several other batches that have been released by the rights group as part of ongoing Freedom of Information Act litigation. Of particular note in the latest trove are documents that show the FBI has been imposing nondisclosure agreements on its staff in order to prevent public disclosure of any information related to the spy technology.