Another Federal Judge Says Cell Tower Dumps Are Unconstitutional

from the when-all-you-have-is-a-dragnet dept

Well, it looks like investigators better go back to doing actual investigations in the Fifth Circuit, rather than just assuming a little paperwork and a whole lot of assistance from service providers is going to do their work for them. For at least the second time in the same state (Mississippi), federal judges have rejected cell tower dump warrants, ruling that these warrants (obviously) cannot hope to meet the Fourth Amendment’s particularity requirements.

The first time this happened was early last year, when a magistrate judge rejected four successive cell tower dump warrants submitted by the FBI. The magistrate was the first level of review in this case. The latest involves the second level of review by a federal circuit judge (h/t Josh Gerstein). This decision does nothing more than affirm the magistrate judge’s rejection of these cell tower dump warrants. (Another rejection of cell tower dump warrants occurred in Nevada roughly six weeks after this one, but that’s in a different circuit so it’s up to the Ninth Circuit Appeals Court to establish this precedent.)

But the origin of these successive rejections goes back a bit further. Bucking its own anything-for-the-cops tendencies, the Fifth Circuit Appeals Court delivered a ruling in August 2024 that said geofence warrants were unconstitutional. That decision relied heavily on the Supreme Court’s 2018 Carpenter ruling — the one that said long-term location tracking (via cell site location info) was unconstitutional.

The Fifth Circuit Appeals Court used the Supreme Court’s Carpenter reasoning to move location info out from under the protection of the Third Party Doctrine. More specifically, it had problems with geofence warrants — warrants that force Google to search everyone’s location records before handing law enforcement a list of probables based on whatever time/date/location restrictions investigators give it.

Turning everyone into a suspect just because investigators don’t actually know who they’re looking for makes a mockery of the Fourth Amendment’s demands for particularity. The government likes to believe that the only particularity needed is the distinct probability that Google stores the location records they’re asking for.

That’s not enough. So, in the Fifth Circuit, precedent says geofence warrants are more likely than not to be rejected for a lack of particularity. This probably explains why the FBI decided to roll its dragnet back to the previous version: the cell tower dump. Rather than ask Google for location data, the investigators asked every cell service provider in the areas where crimes were committed to “dump” all connection records fitting those search limitations. As each warrant was rejected by the magistrate, the FBI made further alterations in hopes of having a warrant approved. But even specifying that the dumps only include cell numbers with multiple hits couldn’t save them.

Here’s how the magistrate judge delivered the news to the FBI last March:

[W]hile the Government has some idea of who may have been involved in one or more of the crimes—the affidavits supporting the warrant applications list seven potential suspects—the Government has not presented probable cause to believe that any particular individual committed any of the specific crimes described. The warrant applications also arguably present probable cause to believe that the searches will reveal the location data of some unknown perpetrators of the crimes. See Mem. at 3 (explaining that affidavits describe “the belief that the cell towers will contain evidence of [who committed] the offenses”). But this is not enough. If the Court were to issue the warrants, it would be authorizing the Government to search the data for every cellular device (including cell phones) of every single individual near the crime scenes without a showing of probable cause as to each individual.

More succinctly (and pithily), here’s why cell tower dumps (and geofence warrants) are unconstitutional:

Stated another way, the Government is essentially asking the Court to allow it access to an entire haystack because it may contain a needle.

As stated above (scroll back a bit because I’m terrible at writing short lead-ins), this new ruling [PDF] presents a final rejection for these cell tower dump warrants. The government can always appeal a magistrate’s warrant rejections, but appealing past this point puts the government back into the Fifth Circuit queue. And if the Fifth Circuit said geofence warrants (which are just a different haystack) are unconstitutional, it’s highly unlikely it will give cell tower dumps a pass.

This decision starts off with a nod to history before immediately bringing everything up to date:

Such intrusions would have been unthinkable to those 55 men gathered in Philadelphia in 1787. Therein lies the problem—the technological resources at the government’s disposal unlock efficient and effective ways to solve crime in the twenty-first century, but they also expose individuals’ whereabouts at all times, including in sensitive places. The government now has the capacity to identify any individual with a cell phone, at any public or private location.

That sort of “efficiency” needs to be checked (as in “checks and balances”). That’s why we have courts. And this court is willing to do what many won’t: refuse to bless constant expansion of government power and information access just because today’s everyone-voluntarily-carries-a-tracking-device reality could not possibly have been foreseen when the Fourth Amendment was put into play.

The government tried to argue that cell tower dumps do not “track” people’s locations like the historical CSLI (cell site location info) at the center of the Supreme Court’s Carpenter ruling. The court says that’s not the point, especially not when the Supreme Court’s ruling is considered in conjunction with the Fifth Circuit’s rejection of geofence warrants.

[T]he Fifth Circuit has recognized that “the potential intrusiveness of even a snapshot of precise location data should not be understated.” Smith, 110 F.4th at 833. See also Chatrie, 146 S. Ct. at 2209-12 (discussing how the length of the search does not determine whether a search occurred). Though tower dumps provide more limited, less-detailed information than geofencing, the inherent nature of this type of search remains corrosive to individuals’ privacy interests.

Furthermore, the government tends to ignore how the Fourth Amendment has been defined since its inception. While the government would prefer its definition of particularity to be limited to “we have probable cause to believe the place searched will contain what’s being searched for” (which is how the government portrays both geofence and tower dump warrants), the courts have long understood the particularity requirement to mean this when it comes to probable cause:

“Probable cause is not a high bar.” District of Columbia v. Wesby, 583 U.S. 48, 57 (2018) (quotation marks and citation omitted). The Government only needs to show that “there is a fair probability that contraband or evidence of a crime will be found in a particular place.” Illinois v. Gates, 462 U.S. 213, 235, 238 (1983).

Cell service provider tower records are neither “contraband” nor “evidence of a crime.” They may help investigators produce a list of probable suspects, but that is not the same thing as contraband or evidence.

Summing everything up, the federal court rejects every one of these warrants and makes it clear the government will need to do something other than ask tech companies and service providers to generate lists of suspects for it — especially when doing so means turning thousands of people into possible suspects just because they happened to be near certain cell towers when crimes were committed.

Law enforcement benefits from tower dumps, as evidenced by recent cases, and this decision may thwart certain criminal investigations. But the gentlemen in Philadelphia knew the Fourth Amendment’s protections would come with costs. The cost to law enforcement is the price we pay to be free from arbitrary Government intrusion into our everyday movements.

It’s that last sentence that’s going to piss off the government the most. All levels of law enforcement seem to believe it’s the public who should be making all the sacrifices when it comes to law enforcement efficiency. This ruling sets the record straight. And if the government wants to take another run at the Fifth Circuit, it certainly can. Given what it’s seen so far, it would probably be better if it didn’t.

Filed Under: 3rd party doctrine, 4th amendment, 5th circuit, cell tower dumps, mississippi, phone records, surveillance