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Technology and Politics Mon Jan 12 2015

Evidence Strongly Suggests CPD Illegally Uses Stingray Technology on Protestors

On Black Friday of 2014, Kristiana Rae Colón — a local Chicago artist recently turned organizer — planned a day of action to honor Mike Brown and protest Black Friday spending. Police surveillance was not really on Colón's mind when she organized the protest and march; her aim was to call attention to the connection between the criminalization of black people and the American capitalist system. But a police-scanner recording from that day reveals what seems to be evidence that Chicago police are illegally accessing data from protestors' phones. And in the recording, Colón is the target of this likely surveillance.

"Apparently someone had gotten access to a police scanner recording where it sounds like [an officer] alongside me referring to me being on my phone, and then asking the person at a remote location whether or not they could tell where I was going," explained Colón. "So the implication is that [the officer] was there, seeing me on my phone, and then asking someone else if they could tell from my phone where I was going."

@SPOTNEWSonIG, a Twitter account that live-tweets information from police scanners, overheard the exchange between the officers that Colón references. What follows is an excerpt from their conversation:

Officer 1800: "One of the girls who's kind of an organizer here, she's been on her phone a lot. You guys picking up any information where they're going possibly?
CPIC: "Yeah, we're keeping an eye on it, we'll let you know if we hear anything."

Chicago's Crime Prevention and Information Center (CPIC) is a fusion center, where two or more law enforcement agencies work together to combat "criminal and terrorist activity." The recording strongly suggests that the officer in the field, "officer 1800," was asking someone at CPIC to access content on Colón's phone.

If the CPD were accessing phone content of protesters, they would be using "Stingray" technology to do so. A Stingray device — the commonly used term for an International Mobile Subscriber Identity (IMSI) catcher — functions as a fake cell tower. It intercepts phone activity as cell phones seek the nearest cell tower, giving law enforcement access to information from any active phones in reach of the device (typically around a 1.5 kilometer radius).

The identity of the officer in the above exchange has been unknown. But another segment of the audio may give a clue as to his identity. On the recording he is referred to as "officer 1800," and another officer, "officer 41," uses his first name:

Officer 41: "Bill, I want to give you a call on your cell."
Dispatcher: "1800, did you copy?"
Officer 1800: "Yeah I did."

When I spoke with Colón, she mentioned that the officer trailing her that day was "Commander Dunn." William Dunn is the commander of the 18th District of Chicago. As Bill is a common nickname for William, this exchange suggests that it was Commander Dunn who saw Colón on her cell and asked remote officers if they could lift information from it.

This recording may provide the final proof needed to confirm that the CPD is using Stingray technology illegally against protestors. But activists in Chicago have long suspected that the CPD uses these devices to monitor them at protests.

Freddy Martinez, a technology activist in Chicago, has two Freedom of Information Act lawsuits in process against the CPD regarding their use of Stingray technology. Martinez believes that the CPD may have been using Stingray devices against protestors as far back as the NATO protests in 2012. There is some evidence to support Martinez's concerns. He noticed that at the NATO protests, "batteries were burning quickly, and messages were not getting through, which seems very consistent with Stingray behavior."

Stingray devices are known for depleting phone batteries quickly because cell towers inform cell phones how much power to operate with. And Stingray devices, which cell phones recognize as a cell tower, tell phones to operate at maximum capacity.

Then last February — ironically at a protest against mass surveillance — Martinez came across what he believed could be more evidence of a Stingray. He was using a phone app that allowed him to see the location of in-range cell towers, and the app showed a tower emerge and move closer as an unmarked police vehicle approached. "We saw cops pull up, it was an unmarked Chicago police green license plate, and then we saw a cell phone tower broadcast, and we thought it was some kind of surveillance device," Martinez recounted. "That's when we started getting even more seemed to be the car itself."

Matt Topic, a civil rights attorney, represents Martinez in his lawsuits. So far, their first FOIA suit has produced the CPD's purchase requests [PDF] for Stingray technology, which go back all the way to 2005. In October 2014, after exposure from the lawsuit, the CPD finally admitted to having purchased cell phone-intercepting devices. Aside from the admission that they own the technology, the department has refused to release any information about how they are using the devices. The CPD did not respond to a request for comment for this piece.

Legally, these devices are supposed to be used with a warrant or appropriate court order to gain information on specific suspects. Originally, the government gave Stingrays to local police forces to aid terrorism investigations. Now, police departments across the country don't want to admit they are using the devices for unrelated purposes. This appears to be what is happening in Chicago.

"One of the things that has been most troubling about the Stingray technology is that it has been so secret," said Ed Yohnka, director of communications and public policy for the Illinois ACLU. The devices give access to all cellular information in range, and since we do not how they are using the Stingrays, the CPD could easily be abusing them. Chicago residents have a right to know how their police force is using their tax dollars.

Due to the CPD's unwillingness to disclose any information, up until now it has been unclear whether their devices could pick up phone content like text messages or conversations, or just more general data such as a person's identity and location. As Martinez explained it, these capabilities can vary depending on the type of Stingray device. One piece of information law enforcement can gain with all Stingrays is the "subscriber ID" of every individual's phone within range. Thus, in the event that law enforcement so desires, they could later use those subscriber IDs to identify every single person in the area of the protest. But the events at the "Brown Friday" protests suggest the CPD has more advanced devices.

In order to expose precisely what constitutional rights the CPD may be violating, Martinez's suit aims to find out how they justify their use of Stingrays to judges. Martinez suspects some judges may not fully understand their capabilities, and that law enforcement may take advantage of this.

The evidence supports this conjecture. Topic explained that they found records showing that the police department has acquired a pen register, which is a device that allows law enforcement access to numbers dialed on a phone. Topic's suspicion is that "the department has relied on pen register/trap and trace orders for the use of Stingrays." Pen registers and trap and trace devices can access the numbers dialed by a phone, but not any of the content going into the phone. This makes them vastly different from Stingrays, which, depending on the model, can access significantly more information. Justifying Stingray use in this way would be illegal.

Another concern is how national law enforcement agencies have justified their use of Stingrays.

"The FBI ... claims that it can use Stingrays in public places without a warrant because people allegedly have no expectation of privacy when using cell phones in public," Topic explained. "I think a lot of people, including the U.S. Supreme Court, would disagree with that claim, and the Court ruled unanimously this past summer that people have reasonable expectations of privacy in the information on their phones." The CPD could be using the FBI's reasoning to take information from phones in public spaces without proper warrants or court orders.

Regardless of the FBI's justification, there is no question that police would be violating civil liberties if they are collecting personal information from cell phones without warrants. Police need a warrant to tap home phones, and cell phones today contain significantly more private information. Additionally, Yohnka believes that under a law passed last year in Illinois, law enforcement needs a warrant not only to collect phone content, but also location tracking data. If they were not taking the proper legal steps to use Stingrays, the CPD would be violating protestors' First Amendment rights to freedom of association and speech, and Fourth Amendment rights against unreasonable search and seizure.

The CPD's suspected use of Stingrays against protestors is troubling on many levels. The militarization of the police in post-9/11 America has been a focus of recent protests. Police forces routinely use military-grade equipment that was designed for the War on Terror, and Stingrays are part of this continuing legacy. At the same time as the US has ramped up the surveillance state, technology has opened up new avenues for law enforcement to access our information. And as of yet, the courts are not equipped to properly regulate its use. The CPD has a long history of illegal and nasty surveillance of activists and black and brown communities; suspicion that they might still be using illegal tactics is far from unreasonable. Thus, in light of mounting evidence, and when placed within the context of state surveillance in the US today, it seems highly likely that the CPD is illegally using Stingray technology against protestors. Chicago residents have a right to know how their police department is using this formidable form of surveillance.

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Justin Case / January 12, 2015 5:37 PM

Beautifully written!

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