from the tons-of-data-in-a-pretty-tight-fence dept
Geofence warrants are just part of day-to-day cop business these days. Rather than moving forward with a list of suspects, law enforcement agencies just ask for data on everyone in a certain area at a certain time and move backwards to probable cause to investigate and arrest.
When a bunch of violent jackasses stormed the Capitol in hopes of disrupting a (no longer peaceful) transition of power, they immediately became targets of federal investigators. The Capitol raid gave investigators a haystack of targets, all generating another, larger haystack of location data. The best place to get this data in bulk is from Google, which really enjoys collecting location data.
Shortly after the insurrection attempt, the FBI issued lots of geofence warrants and began working its way back to a (long) list of suspects. How much data the FBI initially obtained wasn’t revealed until a J6 suspect challenged one of the FBI’s geofence warrants in court. It was a lot.
A filing in the case of one of the January 6 suspects, David Rhine, shows that Google initially identified 5,723 devices as being in or near the US Capitol during the riot. Only around 900 people have so far been charged with offenses relating to the siege.
For the final step, the government sought subscriber information, including phone numbers, Google accounts, and email addresses, for two groups of users. The first was for devices that appeared to have been entirely within the geofence, to about a 70 percent probability. The second was any devices for which the Location History was deleted between January 6 and January 13.
From this, in early May 2021, the FBI received identifying details for 1,535 users, as well as detailed maps showing how their phones moved through the Capitol and its grounds.
The suppression motion filed last month has been denied. The ruling [PDF] from the DC District Court does have a few problems with geofence warrants generally, but not this particular one. (h/t Michael Vario)
First, it says the warrant was not “overbroad,” no matter how much data was sorted through by Google and given to the FBI.
Specifically, Defendant first argues that step one, in which Google provided the Government with an anonymized list of devices falling within the geofence’s geographic and temporal parameters, was overbroad because it required Google to query its entire Sensorvault without probable cause “to search untold millions of unknown accounts in a massive fishing expedition.” But, as the Government points out, the relevant question is not how Google runs searches on its data, but what the warrant authorizes the Government to search and seize. Under Defendant’s theory, no doubt many search warrants and most third-party subpoenas for protected records would be unconstitutionally overbroad because they necessarily would require the third party to search some group of records larger than those specifically requested, whether they reside in a file cabinet or on a server…
The court also says there’s no expectation of privacy in anonymized location data. Referencing the Supreme Court’s Carpenter decision, it says hoovering up massive amounts of data related to hundreds of devices isn’t the same thing as harvesting data targeting a particular device over the space of days or weeks. But even though it comes to this conclusion, it still says geofence warrants have the potential to do damage to Fourth Amendment rights.
Defendant has made no allegation that his or others’ identity was knowable based on the anonymized list produced at step one, and considering the geographic and temporal limitations on the geofence area, it likely would not be possible to deanonymize the list indirectly by cross-referencing more revealing location points—for example, the location where the device spent the night. Accordingly, on the facts of this case, the Court has no basis on which to find that Defendant’s Fourth Amendment rights were implicated at step one.
That said, the Court acknowledges that the scope of legally obtainable anonymous data made possible by geofencing technology could present potentially significant risks to privacy, even if those privacy interests cannot be expressed through Defendant’s challenge to step one of this particular warrant, on these particular facts, under current law.
Finally, it says the supposed overbreadth of the warrant was justified by the scope of the (mass) criminal event.
At the outset, because a warrant’s authorization may be “no broader than the probable cause on which it is based,” Hurwitz, 459 F.3d at 473 (citation omitted), it is necessary to define the scope of that probable cause. January 6 was a unique event in a geographically unusual place such that the scope of probable cause was uncommonly large. Because the Capitol building was not open to the public on January 6 due to the counting of the votes of the Electoral College, the fact of having entered the building during the geofence timeframe itself constitutes evidence of a crime…
Based on an unusual abundance of surveillance footage, news footage, and photographs and videos taken by the suspects themselves while inside the Capitol building, there is much more than a “fair probability” that the suspects were within the geofence area and were carrying and using smartphones while there, such that their devices’ LH would provide evidence of a crime.
Also, the geofence set up by the FBI was extremely unlikely to cast a dragnet full of innocent bystanders, given the Capitol building’s location.
[A]s relevant to the 37 deleted devices, the area around the Capitol is unusual for its lack of nearby commercial businesses or residences. Indeed, while Defendant does not make any specific allegations about any such nearby buildings, the Court’s best estimate is that the nearest is no less than about a quarter of a mile away, or approximately 400 meters. By Defendant’s own admission, the error radius is not known to exceed 387 meters, Def.’s Mot.Suppress at 8, and the error radius for Defendant’s location points in particular extends only as high as 264 meters…
Furthermore, while public streets do appear to be somewhat closer to the geofence area, extensive road closures west of the Capitol, in anticipation of the rally on the ellipse on January 6, including on Pennsylvania Avenue, reduce the likelihood that any stray cars would have been picked up in the geofence error radius…
To its credit, the FBI set up a very tight geofence.
And it could do it in this case because, as the court pointed out, pretty much everyone in the Capitol building that didn’t work there was, at the very least, trespassing on federal property.
And, even if it hadn’t found this particular warrant in this particular case to be constitutional, the court still would have given the government a pass on this one. The good faith exception would apply, especially since the defendant’s particularity arguments seem to focus more on the size Google’s data dump, rather than the warrant approved to obtain the location records from Google.
This denial can be appealed. And maybe it will be. But given the facts of the case here, it seems unlikely the DC Appeals Court will find any reason to overturn the lower court’s ruling. The facts favor the FBI here and the dearth of existing precedent will likely result in future applications of the good faith exception. That doesn’t mean these warrants aren’t worth challenging. It just means this geofence warrant was better crafted than most.