A Guide to Stingray Cellphone Surveillance Technology

What exactly is a “Stingray”? How is it being used to track you? Find out more about this cellphone surveillance technology.

Local police departments and federal agencies around the United States have been making use of cellphone tracking tools for years without warrants. This has been happening since before whistleblower Edward Snowden released his documents to The Guardian and exposed the massive surveillance state that exists around the globe. One of these tools is popularly known as a “Stingray”.

According to the Electronic Frontier Foundation:


The Stingray is a brand name of an IMSI (International Mobile Subscriber Identity) catcher targeted and sold to law enforcement. A Stingray works by masquerading as a cell phone tower—to which your mobile phone sends signals to every 7 to 15 seconds whether you are on a call or not— and tricks your phone into connecting to it.

As a result, the government can figure out who, when and to where you are calling, the precise location of every device within the range, and with some devices, even capture the content of your conversations.


Police officers can use the devices to track your cellphones signal.  Once the signal is located the stingray can provide a general location on the map and police officers can drive around (or in one case, walk door to door) until they get a signal from your phone. This has civil liberties advocates up in arms over the potential for misuse of the tools.

In September, the American Civil Liberties Union asked the Federal Communications Commission to investigate the maker of the Stingray for allegedly misrepresenting information regarding data collection capabilities. According to documents obtained during a Freedom of Information Request by the ACLU of Northern California, Florida-based Harris Corporation misled the FCC about the frequency of use for the Stingray.

In an email from June 24, 2010, an employee with Harris told the FCC that the devices (Stingfish in this case) “purpose is only to provide state/local law enforcement officials with authority to utilize this equipment in emergency situations.” However, the ACLU reports, “records released by the Tallahassee, Florida, Police Department explain that in nearly 200 cases since 2007 where the department used a StingRay, only 29 percent involved emergencies; most of the rest involved criminal investigations in which there was ample time to seek some sort of authorization from a judge.”

Another point of contention is the use of non-disclosure agreements by the Harris Corporation. The corporation and police departments around the nation have been criticized for signing the agreements.  Local police departments have become subordinate to Harris and, even in court cases in front of a judge, are not allowed to speak on the details of their arrangements.  

The technology has made it into the hands of at least 47 agencies in 19 states, according to the ACLU. At least 12 federal agencies are known to use the devices. (Check out this helpful map to find out if your state has them.) The Houston Police Department has received attention recently after multiple reports (here and here) on the departments use of the tools. The HPD has been using some form of surveillance hardware since at least 2007, according to records obtained by Truthout.

At least one judge has now begun requiring law enforcement agencies to specifically ask for permission when using the technology. The Tacoma News Tribune reports that Pierce County’s 22 Superior Court judges “now require language in pen register applications that spells out police intend to use the device.” Police departments have also begun requesting updated equipment that will upgrade “the Stingray system to track 4G LTE Phones”, as AT&T and other cellular providers prepare to shutdown their 2G networks.

In June of this year a Florida judge ruled in favor of the American Civil Liberties Union, forcing the release of  new documents related to police use of stingray technology. The ruling deals with a case where Tallahassee police used stingray to locate a suspected rapist’s apartment without first getting a warrant.

When the police officer involved in tracking the suspect testified in court, the federal government stepped in to demand secrecy, the court obliged, closed the hearing and sealed the transcript. After the ACLU asked the judge to unseal the court transcript based on constitutional First Amendment access to court proceedings, the government attempted to invoke national security privilege by invoking the Homeland Security Act.

The ACLU was able to convince the judge to release the transcript. The documents provide some insight into how the machines work. The use of the technology is still a legal gray area. Some courts have stated that warrants are not required, while other states have yet to rule on the topic.

Here is a short list of known attributes and capabilities of the Stingrays and other IMSI catchers. Please continue to do your own research and learn to protect and encrypt your information. If we do not have a right to privacy, are we truly free?

As long as your phone is on, the Stingray can find you

You do not have to be making or receiving a call for your phone to be tracked

The stingrays force cell phones to send data to the device “at full signal, consuming battery faster.”  A constantly dying battery could be a sign that you are being tracked

Stingrays can be handheld, or vehicle-based. 

Officers are likely bringing them to large protests to gather data on those in attendance

Body Worn” IMSI catchers are coming

 – They are already being used on planes. A version of the cell site simulators, known as DRT boxes, have been used on aircraft by the U.S. Marshals Service. The so called “Dirtboxes” are supposed to be used for criminal investigations but the ACLU says they can collect data from tens of thousands of people on each flight. The civil liberties group has  filed a Freedom of Information Act (FOIA) request regarding the recently exposed program that uses aircraft to gather cell phone data.

Take Action!

The ACLU of California has released a guide for communities to understand law enforcement and government surveillance. “Making Smart Decisions About Surveillance: A Guide for Communities” is designed to make it easier for communities to understand what type of surveillance technology is used in their neighborhoods. Although the guide focuses on California, it offers a variety of tips “for grassroots activists across the country who are concerned about the proliferation of drones, automated license plate readers, facial recognition, and more in their community.”