from the gradually-narrowed-crafting dept

Reverse warrants are being challenged in a criminal case involving a bank robbery in Virginia. These warrants (also called “geofence warrants”) work in reverse, hence the nickname. Rather than seeking to search property belonging to a known suspect, investigators approach Google with a demand for information on all cellphones in a certain location at a certain time and work backwards from this stash to determine who to pursue as a suspect.

Warrants require probable cause. And there doesn’t seem to be much in the way of specific probable cause supporting these fishing expeditions. In this case, a bank was robbed in the late afternoon, resulting in plenty of people unrelated to the robbery being in the vicinity. This is all it takes to turn random people into suspects. And that has gone badly for investigators and, more importantly, innocent citizens on more than one occasion.

Accused bank robber Okello Chatrie is challenging the reverse warrant that led to his arrest and indictment on federal charges. Chatrie hopes that warrant will be found deficient because it will make it easier to undo the damage he seemingly inflicted on himself after he was taken into custody.

In Chatrie’s case, bank cameras showed the robber came and went from an area where a church worker saw a suspicious person in a blue Buick. Chatrie’s location history matched these movements. Prosecutors say Chatrie confessed after officers found a gun and nearly $100,000 in cash, including bills wrapped in bands signed by the bank teller.

Chatrie first moved to suppress this warrant late last year, arguing [PDF] that it’s impossible for a warrant that targets no one in particular to contain the necessary probable cause for the search of Google’s location records.

This is no ordinary warrant. It is a general warrant purporting to authorize a classic dragnet search of every Google user who happened to be near a bank in suburban Richmond during rush hour on a Monday evening. This is the kind of investigatory tactic that the Fourth Amendment was designed to guard against. Geofence warrants like the one in this case are incapable of satisfying the probable cause and particularity requirements, making them unconstitutional general warrants.

His motion also points out that the location info gathered by Google via the Android operating system is far more precise than cell site location info gathered by cell service providers.

[T]he location data available in Google’s Sensorvault is even more precise than the data in Carpenter. Google can pinpoint an individual’s location to approximately 20 meters compared to “a few thousand meters” for cell site location data…

In this case, investigators received “anonymized” data on nineteen cellphones that were in the area at the time of the robbery. From there, investigators determined Chatrie to be the most likely suspect. That’s detailed in the warrant application [PDF] for a search of Chatrie’s Google accounts.

Based upon Google’s return of anonymized information, your Affiant discovered a Google account that: (1) was near the corner of Journey Christian Church prior to the robbery at approximately 4:30 to 4:40 p.m. — the time period [redacted] recalled encountering a suspicious individual wearing reflective glasses in a blue Buick sedan; (2) was near the southwestern corner of Journey Christian Church prior to the robbery at approximately 4:48 p.m.; (3) was inside the Credit Union during the time of the robbery; and (4) immediately left the area following the robbery, leaving from the southwestern corner of Journey Christian Church.

Chatrie filed a supplemental suppression motion [PDF] in May of this year. This one expands on points previously made, as well as adding new information gathered from a few rounds of discovery. It opens with this statement, again characterizing reverse warrants as general warrants forbidden by the Fourth Amendment — something that doesn’t become acceptable just because investigators don’t have any immediate leads.

Local police had no suspects in the robbery of the Call Federal Credit Union, so they decided to enlist Google to sleuth for them. Investigators went to a Virginia magistrate and, without conveying critical information, obtained a staggeringly broad and unparticularized warrant to go fishing in a pool of private location data that most people have never heard of. They demanded the location information associated with all Google users who happened to be in the vicinity of the bank during rush hour on a Monday evening, and thus, caused Google to search numerous tens of millions of accounts at their behest.

As the motion notes, the Supreme Court has said historical cell site data is protected by the Fourth Amendment, requiring the use of a warrant to obtain it. Even though there was a warrant involved here, it did not satisfy the particularity needed to justify this search of Fourth Amendment-protected records.

While the government obtained a warrant in this case, it did not obtain one for Mr. Chatrie’s Location History data. In fact, it did not seek anyone’s data in particular. Rather, the government compelled Google to search everyone’s data in order to develop an investigative lead. This warrant was unconstitutional. It was both overbroad and lacking in particularly, a forbidden general warrant purporting to authorize a dragnet search of Google users. It did not—and could not— satisfy the Fourth Amendment’s probable cause and particularity requirements, rendering it wholly impermissible and void from the beginning.

The government’s response [PDF] portrays Google as nothing more than a nearby resident who could be approached with the proper paperwork to compel it to disclose what it “saw.”

The investigators were correct: Google had been a witness to the robbery. Pursuant to the warrant, Google produced to the United States a small set of records: location information over a two-hour interval of three identified and six unidentified individuals, and limited location information over a one-hour interval of ten other unidentified individuals. This information was sufficient for investigators to recognize that the defendant’s Google account likely belonged to the robber, and subsequent investigation led to his indictment.

The government says the Carpenter decision doesn’t apply because — unlike cell location data gathered by service providers — users must opt in to allowing Google to collect their location data. The argument is an old one: that a person’s agreement to share data with a company is an agreement to share data with a government.

Google could not obtain and store the defendant’s location without his undertaking multiple affirmative acts. He had to opt in to Location History in his account settings, and he had to enable Location Reporting for his phone. The defendant had discretion regarding whether Google stored his location information, and he retained the ability to delete it. And none of the services associated with Google’s storage of location information are indispensable to participation in modern society. The defendant thus voluntarily disclosed his location information to Google, and Google’s conveyance of that information to the United States did not infringe his reasonable expectation of privacy.

The government also argues that a warrant targeting nothing more than anonymized data is still somehow particular. It says warrant affidavits only need to show there’s a probability that evidence will be found in the place searched.

In particular, the affidavit established: (1) that an unknown subject committed an armed bank robbery at a particular place and time; (2) that prior to the robbery, the robber held a cell phone to his ear and appeared to be speaking with someone; (3) that the majority of cell phones were smartphones; (4) that “[n]early every” Android phone “has an associated Google account,” and that Google “collects and retains location data” from such devices when the account owner enables Google location services; and (5) that Google can collect location information from non-Android smartphones if the devices are “registered to a Google account and the user has location services enabled.” From this information, there was a substantial basis for the magistrate to find probable cause to believe that Google possessed evidence related to the robbery.

The defendant argues that the warrant lacked probable cause because it “did not identify any individuals or accounts to be searched because investigators did not know who they were searching for, or even if Google would have relevant data.” However, a warrant for evidence of crime need not identify specific individuals or establish with certainty that evidence will be found—all it must do is establish a fair probability that specified evidence will be found in the place to be searched.

The judge has yet to rule on this suppression attempt. The government’s arguments seek to turn a broad warrant into something that “narrowly” targets what may be a very large data subset collected and stored by Google. The implications of claiming everyone who uses Google’s location services voluntarily waives their privacy right in this information are far-ranging and somewhat opposed to the Supreme Court’s Carpenter decision. While the Supreme Court only delivered a narrow ruling on the warrantless acquisition of several days of cell site location info, it pointedly did not state this was the only way this decision should be applied. Other courts have already found Carpenter’s reasoning capable of covering third-party records not explicitly discussed in that decision.

Finally, also of interest in the reporting on this case is that reverse warrants are the target of legislation in New York. And we have, of all people, the Proud Boys, to thank for it.

“If you are someone who went out on the streets to express your rage, your sadness and your hope that there is a better way to do policing and are then subject to a warrant, I think that would go against everything we are telling people they have the right to do,” said New York state Sen. Zellnor Myrie, a lead sponsor of a bill to ban geofence warrants.

The legislation was prompted in part by a New York Times report that prosecutors sought Google’s cellphone records around the spot where the Proud Boys, a far-right group, brawled with anti-fascist protesters in 2018. Several Proud Boys were later convicted of assault.

If this challenge ends up in a federal appeals court, more attention will be drawn to these questionable warrants that allow investigators to treat everyone in an area as a suspect by leveraging data many cellphone users may not realize is being collected and stored. And, because this is a relatively new investigative option, judges aren’t being provided with all the details needed to make informed decisions, which is going to result in even more collateral damage in the future if courts don’t start doing something about this now.

Filed Under: 4th amendment, okello chatrie, privacy, reverse warrant

Categories: Technology