The Fifth Circuit Shuts Down Geofence Warrants—And Maybe A Lot More

An astonishing ruling, and one that creates splits on two differerent issues.

Once in a while there is a court ruling on the Fourth Amendment that just makes my jaw drop.  The Fifth Circuit had such a ruling last Friday, United States v. Jamarr Smith. The case creates a split with the Fourth Circuit on one important issue, and it creates another split with the Colorado Supreme Court on an even more important issue.

The new case is about the Fourth Amendment limits of geofence warrants, which are warrants to access location information for users who have opted into having Internet providers retain location history.  The Fifth Circuit makes two important holdings. First, accessing any amount of geofence records is a search under an expansive reading of Carpenter v. United States. That's the issue that creates the split with the Fourth Circuit in United States v. Chatrie.  As I noted just a few weeks ago, Chatrie held that accessing such records is not a search in the first place, at least if the records sought are relatively limited in scale. The Fifth Circuit expressly disagrees.

Second, and much more dramatically, the Fifth Circuit rules that because the database of geofence records is so large, and because the whole database must be scanned through to find matches, the Fourth Amendment does not allow courts to issue warrants to collect those records. In legal terms, it is impossible to have a warrant particular enough to authorize the surveillance.  The government can't gather these kinds of online records at all, in other words, even with a warrant based on probable cause.  This holding conflicts with a recent ruling of the Colorado Supreme Court, People v. Seymour, and more broadly raises questions of whether any digital warrants for online contents are constitutional.

There's obviously a lot going on in this new decision.  Because I have blogged about the search issue several times before, including just last month, I want to focus this post instead on the second ruling—that geofence warrants are not permitted, even with probable cause.  I think this ruling is wrong, and that it's very important for it to be overturned.  This post explains why.

I. The Legal Context

First, some context.  When the government obtains a geofence warrant, the provider is ordered to provide data matching the geofence.  The warrant will call for the provider to hand over records made in a particular window of time and that recorded locations in a particular physical area.  The provider has a database consisting of location records of the accounts that opted into the service, and the provider—here, Google—searches through the database looking for a match with the records sought in the warrant.  Google calls this "Step 1" of its geofence warrant process.  If Google finds matches, it then goes through further steps that ultimately gives the government records that are responsive to the warrant.

Warrants have to be particular, and particularity requires two things.  First, the place to be searched must be particular.  For example, the government can't get a warrant to search an entire city block, or to search the entirety of an apartment building with lots of independent units. The place that is searched through has to be smaller than that, like a single business or (more often) a single house.   Second, particularity requires a particular description of the thing to be seized. The government can only take the evidence or contraband that is evidence of the crime.

Most discussions of particularity are about the particularity of the things to be seized.  Prior discussions of particularity for geofence warrants have focused on that. The issue has been, how broad can the warrant can be in terms of how much time and space the warrant can cover?  A geofence warrant orders the provider to hand over records that were of users in a particular area for a particular span of time.  A warrant might cover, say, within a mile of where the crime occurred, for, say, the 30 minutes before the crime occurred and up to 30 minutes after it.  But that kind of particularity is about how broad the records can be that the government gets.

The issue in Smith is about the first kind of particularity—the place to be searched.

II.  The Warrant Ruling

Smith rules that the database that Google has created, through which Google looks for matches with the data described in the warrant, is just too big to search.  Google combines all of its location records from all of its users worldwide into a single database, covering an estimated 592 million people, that it calls Sensorvault.  When Google queries that Sensorvault database, the Fifth Circuit holds, it is scanning through a "place" too big for the Fourth Amendment to allow.

Here's the entirety of the court's above-the-line analysis on this issue, with italics in the main text in the original:

When law enforcement submits a geofence warrant to Google, Step 1 forces the company to search through its entire database to provide a new dataset that is derived from its entire Sensorvault. In other words, law enforcement cannot obtain its requested location data unless Google searches through the entirety of its Sensorvault—all 592 million individual accounts— for all of their locations at a given point in time. Moreover, this search is occurring while law enforcement officials have no idea who they are looking for, or whether the search will even turn up a result. Indeed, the quintessential problem with these warrants is that they never include a specific user to be identified, only a temporal and geographic location where any given user may turn up post-search. That is constitutionally insufficient.

Geofence warrants present the exact sort of "general, exploratory rummaging" that the Fourth Amendment was designed to prevent. Coolidge v. New Hampshire, 403 U.S. 443, 467 (1971); see also Riley, 573 U.S. at 403; Geofence Warrants and the Fourth Amendment, [Kerr note: A student note cited 10 times in the opinion] supra at 2519. In fact, Google Maps creator Brian McClendon has called these warrants "fishing expedition[s]," and explained that Google employees originally assumed law enforcement would only seek Location History data on specific people—a reality that did not come true. Jennifer Valentino-DeVries, Tracking Phones, Google Is a Dragnet for the Police, N.Y. Times (Apr. 13, 2019), https://perma.cc/NCF3-H5DP. "Awareness that the government may be watching chills associational and expressive freedoms." Jones, 565 U.S. at 416 (Sotomayor, J., concurring.). And, when these core rights are at issue, the warrant requirement must "be accorded the most scrupulous exactitude." See Stanford, 379 U.S. at 485.

Here, the Government contends that geofence warrants are not general warrants because they are "limited to specified information directly tied to a particular [crime] at a particular place and time." This argument misses the mark. While the results of a geofence warrant may be narrowly tailored, the search itself is not. A general warrant cannot be saved simply by arguing that, after the search has been performed, the information received was narrowly tailored to the crime being investigated. These geofence warrants fail at Step 1—they allow law enforcement to rummage through troves of location data from hundreds of millions of Google users without any description of the particular suspect or suspects to be found.

In sum, geofence warrants are "[e]mblematic of general warrants" and are "highly suspect per se." Geofence Warrants and the Fourth Amendment, supra at 2520; Amster & Diehl, Against Geofences, [Kerr note: A student note cited 13 times in the opinion] supra at 433– 34; Chad Marlow & Jennifer Stisa Granick, Celebrating an Important Victory in the Ongoing Fight Against Reverse Warrants, ACLU (Jan. 29, 2024), https://perma.cc/SC2R-S7PJ ("The constitutionality of reverse warrants is highly suspect because, like general warrants that are prohibited by the Fourth Amendment, they permit searches of vast quantities of private, personal information without identifying any particular criminal suspects or demonstrating probable cause to believe evidence will be located in the corporate databases they search."); Chatrie (App.), 107 F.4th at 353 (Wynn, J., dissenting) ("[A] [geofence] warrant is uncomfortably akin to the sort of 'reviled' general warrants used by English authorities that the Framers intended the Fourth Amendment to forbid.").

This court "cannot forgive the requirements of the Fourth Amendment in the name of law enforcement." Berger v. New York, 388 U.S. 41, 62 (1967). Accordingly, we hold that geofence warrants are general warrants categorically prohibited by the Fourth Amendment.

The court does go on to say the good-faith exception applies here and so there is no suppression, but that particular ruling is tiny potatoes.  It's the warrant ruling that is the serious biggie here.

III. My Take On Why The Warrant Ruling Is Wrong

I think the Fifth Circuit's warrant ruling is wrong— and not just wrong, but basically bananas.  Here are three reasons why, together with an explanation of why the stakes of the case are so high.

First, the ruling conflicts with the Supreme Court's precedents on warrant particularity.  The Fifth Circuit's decision relies heavily on two law student notes. It quotes an ACLU blog post. It also quotes a Wall Street Journal article.  But it doesn't even mention the Supreme Court's relevant caselaw on warrant particularity. And that authority, it seems to me, conflicts with the Fifth Circuit's ruling.

An especially relevant case is United States v. Karo, which considered the Fourth Amendment implications of installing and monitoring a location tracker in physical space.  The Supreme Court had previously ruled that no search occurred when the tracker recorded beeper locations while the beeper was out on public roads. Karo ruled that a search did occur when the tracker was brought inside a home and registered locations inside.

The relevant part of Karo is the Court's reply to an argument the government made about warrant particularity. No warrant was needed to use a tracker, the United States argued, because it wasn't possible to draft a particular warrant.  After all, the whole point of using the beeper is to find the location of the item that the suspect has, and thus to locate the suspect.  If you don't know where the beeper is, then you can't specifically describe the place to be searched. And if you can't specifically describe a place to be searched, you can't get a warrant. Thus, the surveillance should be allowed without a warrant, the government reasoned.

The Supreme Court responded by rejecting the premise and explaining how to draft a warrant in such cases to match the Fourth Amendment particularity standard:

It will still be possible to describe the object into which the beeper is to be placed, the circumstances that led agents to wish to install the beeper, and the length of time for which beeper surveillance is requested. In our view, this information will suffice to permit issuance of a warrant authorizing beeper installation and surveillance.

It seems to me that this controls Smith, too.  The warrant problem in Karo was a lot like the problem in geofence warrant cases.  The "place to be searched" is basically everywhere.  The search would occur wherever the beeper happened to go.  But instead of saying that no warrant could be obtained, the Supreme Court in Karo articulated a way to draft warrants to allow the surveillance.  The place to be searched was the object into which the beeper is to be placed, with the particularity being provided by the length of time for which beeper surveillance is requested.

I personally don't think geofencing is a search in the first place, as I have argued before.  But if we are to say that geofencing is a search, it seems to me that the approach from Karo should govern here.  Following Karo, the particularity should be provided by a description of the database into which the query is made, combined with the length of time (and amount of geographic space) the warrant covers.  We can argue about how long a period is permissible, and how big a geographic space is permissible.  But the idea that there is a cap on the size of the database seems hard to square with Karo.

Unfortunately the Fifth Circuit doesn't discuss Karo, so we don't know what the panel's response to it might be.

Second, the warrant ruling seems hard to square with Carpenter v. United States.  The notion that warrants cannot be obtained to search through particularly large databases also strikes me as hard to square with the Supreme Court's ruling in Carpenter, the case on which the Fifth Circuit's own search ruling is based.

Carpenter made two important rulings.  First, the Court ruled that access to at least long-term cell-site location information (CSLI) is a search.  Carpenter then took on a second issue: Does the government need a warrant to compel CSLI, or can it be compelled with just a subpoena?  The Court ruled that a warrant was required:

Having found that the acquisition of Carpenter's CSLI was a search, we also conclude that the Government must generally obtain a warrant supported by probable cause before acquiring such records. Although the ultimate measure of the constitutionality of a governmental search is 'reasonableness,' our cases establish that warrantless searches are typically unreasonable where a search is undertaken by law enforcement officials to discover evidence of criminal wrongdoing. . . .

This is certainly not to say that all orders compelling the production of documents will require a showing of probable cause. The Government will be able to use subpoenas to acquire records in the overwhelming majority of investigations. We hold only that a warrant is required in the rare case where the suspect has a legitimate privacy interest in records held by a third party.

Carpenter obviously contemplates warrants for non-content user account records. That was the whole premise of the Carpenter's warrant ruling.  The Supreme Court, faced with a decision about what level of protection the Fourth Amendment requires, picked the warrant rule over the subpoena rule.

The Fifth Circuit's ruling in Smith seems hard to square with that.  The nature of the Carpenter ruling is that queries for Carpenter-protected records will generally be through massive databases. Under the Fifth Circuit's decision, however, the Supreme Court's warrant holding in Carpenter was basically meaningless.  Most searches for Carpenter-protected data will be through massive databases.  If the governing law is that a warrant is sufficient (the Supreme Court rule) except when the database queried is massive (the Fifth Circuit's rule), in practice that amounts to a rejection of the Supreme Court's holding in Carpenter.

Third, whether the suspect is known is constitutionally irrelevant.  The Fifth Circuit's opinion is very concerned with the fact that the suspect in a geofence warrant case is unknown.  That is, the whole point of the warrant is to identify the suspect.  The Fifth Circuit treats this as especially troubling.  But I don't get why.

Just a matter of doctrine, it's obviously irrelevant that the government doesn't know who the suspect is yet.  Think about a case like Zurcher v. Stanford Daily., where the Supreme Court upheld a warrant to search a newspaper office to look for photos that the paper's photographers might have taken, all to help identify campus protesters.  The fact that the police didn't know who the suspects were was irrelevant.

And it's hard to imagine a contrary rule.  I mean, most warrants for Internet investigations are to identify a suspect.  The government will trace someone's online conduct, and they'll then try to gather information to identify who was behind the account activity.  Maybe someone sent an online threat from an anonymous account, and the government will get a warrant to search the online account to figure out who sent the threat.  Maybe someone downloaded child sexual abuse material (CSAM) using a particular account, and the government will get a warrant to search the account to know who downloaded it.

The primary point of the warrant in these cases is to find the unknown person who committed the illegal act.  If there is some legal reason that not knowing who the suspect is and getting warrants to find out makes these routine warrants suspect, I cannot fathom what that legal reason might be. The Fifth Circuit does not mention any.

Fourth, the stakes of this case are immense, going way beyond geofence warrants, encompassing most law enforcement and national security surveillance involving the Internet.  I started this long post by saying that the warrant ruling was more important than the search ruling. That's not to say the search ruling isn't important!  But if the search ruling has case-of-the-week importance, the warrant ruling has case-of-the-year importance.

Why is that?  It has nothing to do with geofence warrants.  Instead, it has to do with all the other digital warrants.

By it very nature, gathering digital evidence often means looking for matches through large amounts of data.  There's a query looking for responsive files, and the "hit" on responsive files is the evidence collected.  The question is, what is "searched"?

I remember first thinking about this question in the late 1990s, back when I was at DOJ, in the context of Internet pen registers. If there's a stream of Internet traffic going by, and you have the program scan for a match of non-content records (say, a packet header of a packet sent from a particular IP address), the government is inherently scanning through all of the traffic going by.  I mean, they don't want that other stuff.  They only want the extremely tiny proportion of data that is actually responsive to the court order.  But as I pointed out in this 2003 article, it's the nature of the technology that they have to scan through the haystack to find the needle.

The fundamental question was, if you have a filter scanning through data for a match, is the scope of the search defined by what dataset was scanned through, or is the scope of the search defined by the filter setting?   The stakes are high.  If a filter is scanning through a pipe of Internet traffic streaming by, looking for a packet header, that was either not a Fourth Amendment search at all (as the filter was set to only collect packet header data) or a massive search so broad that any warrant purporting to authorize it was an unlawful general warrant (as all of the data of thousands or in some cases millions of people was scanned).

The conclusion I came to is that the filter setting had to be the key.  Otherwise, the fortuity of the technology rendered essentially all data collection illegal.  It was an instinct that today I would think of as equilibrium-adjustment. As I thought of it then, it just didn't make sense that the technological coincidences of how the Internet was designed and how data is stored would have the effect of dramatically transforming Fourth Amendment protections.

There ended up being not a lot of caselaw on this particular question, as defense counsel did not try to argue the point.  The key case that comes to mind is the Colorado Supreme Court's ruling last year in People v. Seymour, where the Court rejected the claim in the context of a reverse keyword search warrant.  The warrant required Google to look through its entire database of stored queries to see who had made a particular query, and the defense argued that this was a general warrant because it had to scan through the whole database to find the responsive hit. Seymour disagreed:

Seymour asserts that a reverse-keyword warrant of the sort at issue here is necessarily overbroad because the "place to be searched" is Google's entire database, including every user account. True enough, at least in a broad, technological sense. But when analyzing the legality of a warrant, the "ultimate touchstone" is reasonableness. Brigham City v. Stuart, 547 U.S. 398, 403 (2006); see also People v. Davis, 2019 CO 24, ¶ 15, 438 P.3d 266, 269. Here, the scope of the place to be searched strikes us as reasonable when we consider the filter provided by the search parameters set forth in the warrant. Yes, those parameters establish what the government ultimately seized, but, as we discuss further below, they also serve to dramatically reduce the intrusiveness of the search.

The reason I raise all of this is that the Fifth Circuit's ruling, although announced in a case that happens to be about geofence warrants, is about a lot more than that.  It's about CSLI.  It's about pen registers. It's about keyword searches.  It's about pretty much all database queries.  They all have this common feature that the Fifth Circuit found objectionable.  Just create a data source big enough—how big, we don't know, but big—and then it can't be searched, even with a warrant.

The Supreme Court has reserved the "no warrant" rule for extreme facts.  The only example the Supreme Court has identified is a warrant to force a person to endure invasive surgery for evidence that could kill them and isn't important evidentiary purposes, anyway, an exception to the general warrant rule carved out by Justice Brennan in 1985 in Winston v. Lee.  Extending that to big database queries, well, that's a pretty big change.

I'll end with a prediction. In a few days there will be a news story about some national security surveillance program that either stopped, or paused, or at least was the subject of a lot of emergency meetings.  You won't be able to tell from the news story what the program was, or what was the cause of concern. But the untold explanation will be a roomful of very worried national security lawyers trying to figure out what the heck to make of the Fifth Circuit's ruling in United States v. Smith.

UPDATE: I have made slight corrections to the post since initially publishing, correcting the date of the opinion and that the ACLU document cited was a blog post and not a press release.

Comments

[Armchair]

It does seem surprisingly broad.

The search is asking one company to search its database. An admittedly large database, but still...how large a database is too large?

If the FBI has a report of a terrorist on an airplane by the name of John X, and asked the airlines to search their databases for any current or old passengers by that name...is that too broad?

If the FBI had a report of a drug smuggling operation that was keeping money with Bank of America, and asked for accounts with their name on it...it's a database search again.

Let's go smaller. You've got a home computer (or 20) with a large database on it. The FBI seizes it because they believe there's evidence of a crime on it. Can they search that database if it has a million entries? What if there are two million entries? 10 million? 1 Trillion? At what point aren't they allowed to search the database?

[Krayt]

That's what a warrant lists -- here are the things to be searched for, amongst a much larger pile of junk and papers in your home.

That's different from gathering up a list of everyone who was within 1800 yards of some event, so you can investigate each further.

[Armchair]

It's not quite the same. It's the area being searched that's at issue.

Imagine if there's this proverbial list of everyone within 1800 yards on a piece of paper at your house. The FBI could certainly get a warrant for that. But if the list was "somewhere" in one of the several hundred offices in the United States your company owned. That might be harder to get a warrant for.

By analogy, if that list was on a small database in your home computer.,,,no problem. But if the same list was in a large database, now it's off limits.

[JesusHadBlondeHairBlueEyes]

You should update your example with something more realistic:

The FBI had a report of a parent who spoke out at a school board meeting...
The FBI had a report of a politician who filed impeachment complaints against a Democrat...
The FBI had a report of a journalist who exposed Democrat corruption...
The FBI had a report of a Christian who prayed near an abortion clinic...
The FBI had a report of a conservative who posted mean things about Biden on Facebook...

[David Nieporent]

You should feel bad about your choices as a human being, and stop posting here.

[JesusHadBlondeHairBlueEyes]

You don't like seeing facts, do you Talmudian?

[Riva]

I have no issue responding to Nieoporent’s usual BS but this “Talmudian” crap crosses a line.

[JesusHadBlondeHairBlueEyes]

How so?

What line?

[shawn_dude]

From a technical standpoint, searching a million records on a key value like an IMEI number is trivial. Geofencing complicates that a bit more, but not by much given that the companies who store this data already use similar techniques to support their marking businesses. Google is always asking me how I liked X business not long after I visited it or someplace nearby.

This kind of search could be used, for example, to determine if a suspect was at the DC Capitol on January 6th.

[Estragon]

“This kind of search could be used, for example, to determine if a suspect was at the DC Capitol on January 6th.”

Indeed, I suspect this was a key— if unstated— factor here.

[Armchair]

"searching a million records on a key value like an IMEI number is trivial."

While I agree, the court seems to think differently.

[Michael P]

Are location records really accurate enough to say someone was at the Capitol rather than at the U. S. Grant Memorial, Garfield Monument, or Botanic Garden that are not even across the street from the Capitol? Even if so, isn't that a special case of the Capitol having its own dedicated cell towers, and not the case for most places?

I am not super current on this, but fairly recently, typical cell tower sectors were roughly triangular (120 degrees wide at the tower end) and at least hundreds of yards in length (from the tower) under even the simplest transmission models -- reflections and obstructions would make the effective shape much more complex. Merely checking what phones use a sector would only localize someone to a Capitol-size area when it's a mini- or micro-cell set up for a given building or event.

[Absaroka]

Not something I keep up on either, but 'location services' uses things other than cell tower triangulation: gps, proximity to wifi, yadda. There is new stuff coming with the potential for 30 centimeter accuracy, apparently. Below is a link to a stackexchange thread with links to other sources. IIUC the providers (apple, google) really want to know when you walk thru a store door, or for that matter whether you are in the housewear or shoe department.

Stackexchange

[John F. Carr]

It is easy to design the database of locations so that it is indexed by location as well as user. Let's use grid squares for a simple example. If a location record comes saying (Suspect phone is at 41.3N, 80.2W) it is added to the bucket for (41 to 42 degrees north, 80 to 81 degrees west). It is also added to the personal location history for Suspect.

Now when the FBI says "give me everybody near (41.3, -80.2)" Google only has to search through that one degree by one degree square. And you can make the grid squares smaller, or use a fancier data structure, to further reduce the time spent searching and the number of extraneous records checked.

The result is the same as searching billions and billions of location records, but it happens much faster. That's how database indexing works in general. Any type search term you expect to use has an index table allowing fast searching on that type of search term. You can also create tables showing relationships between two fields to speed up more complicated queries.

Google's lawyers might say "we searched through billions and billions of records". But the computer may have taken a shortcut.

Does the Fourth Amendment care whether "tell me everybody at 1600 Pennsylvania Avenue on October 20, 1973" triggers an optimized or brute force search?

[Armchair]

You could design it that way, but the opposite is also true.

If Google (or any other company) didn't want to do the search warrant, they could simply say "the database isn't organized like that, it's indexed by "x" it's too broad a search"

[jb]

Two points:

1) Google has already redesigned the way location tracking works such that it's not going to have the location data centrally anymore. Instead it will just reside on your personal device. (This is rolling out now; I think they're going to be deleting all of the data by the end of the year.)

2) I presume in the old system they must have had data indexed both ways because otherwise these searches would be ludicrously expensive.

[Brett Bellmore]

That really is the ultimate answer to these sorts of warrants: Stop retaining the data, which they really had little good excuse to have retained to begin with.

[shawn_dude]

Google bases its marketing partly on location. Unless they're giving that up, they have a different method to do the same thing. And if not Google, AT&T, T-Mobile, and other cell tower operators store this information.

[jb]

For a real-time query they can show location-targeted ads without storing your location, they just need to know where you are right now. It's definitely possible that they'd still store location when you're actually doing stuff with Google (e.g., you do a search) but that's very different from something like Timeline where they've been storing your location even if you're not interacting with a device at all.

But yes, the cell phone companies are HORRIBLE when it comes to this stuff. They not only store your location, but they've been caught several times selling the data. (Despite popular misunderstanding to the contrary, the tech companies don't sell the data they have about people--instead they use it to target ads.). As far as I know, there's not any way to opt out of this.

[Armchair]

1) While fine in this particular case, the question of "other databases" is a significant question here.

[Absaroka]

"Google’s lawyers might say “we searched through billions and billions of records”. But the computer may have taken a shortcut."

I'd be ... flabbergasted if that data was in a flat file.

[John F. Carr]

It doesn't have to be a flat file to require a brute force search. It has to be designed without considering the particular query. I remember hanging my school's computer account database for 20 minutes by submitting a query for which there was no index. I think I asked for "all lists containing, recursively, account name X". The nonrecursive directly containing relation was fast. "Give me all the users in list Y, recursively expanded" was fast. The database admin had to do some dbadmin magic to make my query run fast.

[DaveM]

I quite agree with this point, and in fact off the top of my head I can imagine several ways that Google can limit database queries so the government doesn't have to look at everybody just to find the one person they're interested in.

This is merely a technical challenge. And not a very big one.

My vote would be to do the searches in two stages: in the first stage, Google exports all the data in the geographic area. This export doesn't look at anything other than map coordinates. In the second stage, the government searches the exported corpus. An entirely reasonable and technically feasible solution.

We don't have to surrender every atom of data we have or will ever have just so a prosecutor can catch a bad guy.

[Noscitur a sociis]

I’m not sure I understand the difference between your proposal and what happened. The government only got the (anonymized) information from the time and geographic window it requested. The “issue” is that in order to produce the list, Google had to search each individual record it had to see whether or not it fell within that scope.

[shawn_dude]

Well... that's not exactly true. Technical designs are often described with metaphors to non-technical people but those metaphors aren't useful for looking at the details.

IMEI or other key identifiers are going to be indexed into the database (assuming a relational database conforming to at least third normal form.) Scanning an index doesn't really search each individual record (where "record" is assumed to mean all the other data associated with that key value.) The index is just a key value and a pointer to the record. Think of it like (metaphor!) the labels on file folders in a file cabinet. Is looking at the identifier on the tab considered a search of the entire file without actually pulling it out and reading it? [IANAL] This is the same for geolocation data assuming it's also indexed--which it very likely would be.

So doing a database search on a geofenced area and collecting all the key values associated with that area wouldn't necessarily require a detailed search of records not implicated by the warrant. But I caveat that with acknowledging that I don't know the legal definition of "search" and I'm basing it on my experience with designing relational schemas for complex datasets.

[Noscitur a sociis]

That’s true, but it’s orthogonal to my point in response to DaveM, which is that the government doesn’t ever see anything except the responsive results (i.e. an anonymized list of accounts that had hits in the date and time range specified). Page 16 of the opinion has a screenshot of what that looked like in this case. So unless I’m misunderstanding, the technical challenge has been met and the government is already getting only what DaveM is proposing they be limited to, and apparently that isn’t good enough.

Edit: Also to respond to you directly, the warrant doesn't (and I doubt it could legally) require Google to conduct its search for responsive records in any particular way. I think that it's probably likely that Google has the information stored in something along the lines you're talking about (I'm not sure if the details have been publicly disclosed), but in theory there's nothing stopping them from being in full compliance with their obligations by having human employees literally review the data for each individual account.

[Lee Moore]

Not having the smallest clue about the law I can only comment on the logic - of the what is searched bit.

If we were not talking about computers but stuck with Prof Kerr’s analogy of searching a haystack for a needle, it seems, ah, counterintuitive to conclude that the searcher is searching the needle and not searching the haystack.

He may be searching FOR the needle, but the thing he is searching is the haystack.

Unsurprisingly I was not entirely convinced by Prof Kerr’s reason as to why his strange answer was the right one, which seemed to be one of those reading back from the consequences ones. This must be right because the contrary view would by REALLY inconvenient for the government.

I think Prof Kerr mentioned that he used to work for the DOJ. That bit I found convincing.

[Armchair]

I think a better example is one of an expansive property.

Imagine the FBI is searching for a kidnapping victim. They narrow the victim's whereabouts to a square mile of land.

Now, if this square mile of land was in a city, there may be hundreds of different houses with different owners. The FBI would need to get a search warrant for a particular house, it would be very difficult for them to get a search warrant for all of the houses.

If on the other hand, this square mile of land was in the country, it may be owned by a single family, with a farm, with multiple outbuildings. In such a case, the FBI would find it much easier to get a search warrant for that property. Would the FBI need to specify the "specific" outbuilding? Or could they get a general search warrant for the entire property and the main house, and any caves or gullies found?

It's a square mile of land being searched. What's the difference though, in terms of a search warrant?

[Lee Moore]

I may well be missing the point, but your example seems to be on Prof Kerr’s discussion of the question – when you specify something to be searched how vast can your specification be ? To the extent that reasonableness is legally relevant I can certainly see that specifying one square mile of city is vaster than one square mile of the boonies.

But my query was on one of his later points, which I understood to be suggesting that when you search a database (aka haystack) for items which match your chosen filter (aka needles) you are not searching the database, you are searching the responsive records. As I say I may have misunderstood his point, but it seemed unconvincing to me. The way he worded it was :

The fundamental question was, if you have a filter scanning through data for a match, is the scope of the search defined by what dataset was scanned through, or is the scope of the search defined by the filter setting?

Which seems like changing the subject to me. How can the “filter settings” be the “scope of the search” ? You’re not searching the filter settings, you set them ! You’re searching the data (all of it) for records that match your filter settings.

So, turning it into a concrete example, suppose you are searching for a padlock with the combination 2906 in a large box of padlocks (say 1000 of them) set to various combinations. You try them all for 2906, and yay you get one. What did you search ? The box. Obviously. Prof Kerr woud say (if I understand him) that ”
the scope of the search was defined by the combination 2906.” Well maybe so, but that’s just dodging the question of what it was that was searched. Which was the box.

Or if you prefer it's like searching a filing cabinet for letters from Mr Abdul Masood. Prof Kerr would say that "Mr Abdul Masood" defines the scope of the search because that is your filter. But what you're searching is the fiing cabinet.

[Stephen Lathrop]

If there is some legal reason that not knowing who the suspect is and getting warrants to find out makes these routine warrants suspect, I cannot fathom what that legal reason might be.

Professor Kerr — Perhaps the legal reason is discernible from history, and a close reading of the 4A:

The right of the people to be secure in their persons, houses, papers, and effects, against unreasonable searches and seizures, shall not be violated, and no Warrants shall issue, but upon probable cause, supported by Oath or affirmation, and particularly describing the place to be searched, and the persons or things to be seized.

Seems like that, “or,” towards the end is, in your reading, doing a lot of work to elide the, “persons,” mentioned at the outset. My reading, in historical context, is that it would be less disruptive to suppose a failure to distinguish with two commas the persons from the things. Thus:

“and particularly describing the place to be searched, and the persons, or things, to be seized.

Nothing else seems to me to be consistent with the larger meaning of the amendment in historical context—to guard ability of people, “to be secure in their persons,”

Read it without my hypothetical commas, and the, “or,” accomplishes a purpose to afford the, “persons,” no protection at all. That seems to be the way you read that text, or perhaps the Court decisions, but I doubt anyone could support such a reading with historical evidence from the founding era. More generally, isn’t it also an affront to history to suppose a warrant can properly be used to discover the probable cause needed to justify itself?

If, as you insist, prior Supreme Court case law posits reasoning to overturn historical context, shouldn’t that at least be mentioned forthrightly? Or do you suppose the drafters and ratifiers of the 4A were unconcerned about protecting, “persons?”— including persons under scrutiny initiated without probable cause? I suggest if that were an accurate historical reading, then the role of Samuel Adams in this nation’s history would have been far smaller than it turned out to be.

As always, I thank you for your thoughtful posts, and for your willingness to engage with commenters.

[Noscitur a sociis]

Yes, the amendment certainly recognizes a “right of the people to be secure in their persons…against unreasonable searches and seizures”. But that doesn’t seem especially relevant to this issue, since the execution of this warrant didn’t involve searching or seizing any persons.

More generally, isn’t it also an affront to history to suppose a warrant can properly be used to discover the probable cause needed to justify itself?

I think you’re misunderstanding. There needs to be probable cause that the execution of the warrant will provide evidence of a crime. There doesn’t need to be probable cause that a specific person committed that crime.

Or do you suppose the drafters and ratifiers of the 4A were unconcerned about protecting, “persons?”— including persons under scrutiny initiated without probable cause?

I have too much respect for the founders to think they had such a silly concern, but if they certainly didn’t put any such requirement in the fourth amendment. I’m also not sure why you’re bringing it up, since the defendants in this case didn’t come under scrutiny Neil after there was probable cause that they committed the crime.

[David Nieporent]

Nothing else seems to me to be consistent with the larger meaning of the amendment in historical context—to guard ability of people, “to be secure in their persons,”

Read it without my hypothetical commas, and the, “or,” accomplishes a purpose to afford the, “persons,” no protection at all. That seems to be the way you read that text, or perhaps the Court decisions, but I doubt anyone could support such a reading with historical evidence from the founding era. More generally, isn’t it also an affront to history to suppose a warrant can properly be used to discover the probable cause needed to justify itself?

I don't even understand this comment. Of course the 4th amendment — with or without extraneous commas — protects persons, but since people do not live in databases (typically), no person was being searched or seized by searching the database.

[Commenter_XY]

Wow, wow, wow! Thanks for this, Professor Kerr.

The impression I was left with from your description of the 5th circuit's reasoning was the Court seemed intent on stopping warrantless digital fishing expeditions by the Federal government. I am not sure focusing on filtering is the answer to stop warrantless digital fishing expeditions. You're making a trade-off to let the Feds data mine their way to an indictment, in order to get that equilibrium you wrote about.

Is there another approach that gets us where the 5th Circuit appears to leave us: NO warrantless digital fishing expeditions allowed unless particularity is addressed? If filtering is not the answer, what else is there.

I want to thank you for your great posts on 4A (and the odd historical corners of legal history); it helps me understand as a citizen what the law actually means.

[Noscitur a sociis]

I think you might need to read the post again. This entire point is that this holding says the government can’t conduct these searches even if they do get a warrant.

[MollyGodiva]

"Opt in"? Where did Google ask me to opt in to them saving my every move? They don't. They automatically track you and make it hard to not be tracked. Same with every other tech company, and many non-tech companies. The whole "data willingly given to their parties" BS needs to go away.

[jb]

https://www.forbes.com/sites/zakdoffman/2024/06/07/google-location-tracking-on-android-and-iphone-ios-stops-in-180-days/

[Bubba Jones]

Would it be permissible to interview and investigate every single person who passed within a mile of a store, across an hour time span, in order to determine who might have stolen something?

That's effectively what these geofence searches are doing.

And what records are they searching? People who have opted in to letting Google Maps track their locations at all times?

Reminder to turn off your phone when committing crimes.

[Noscitur a sociis]

Would it be permissible to interview and investigate every single person who passed within a mile of a store, across an hour time span, in order to determine who might have stolen something?

Yes? Why in the world wouldn’t it be?

[Brett Bellmore]

Well, for one thing, if a thousand people passed within a mile of the store, (Maybe plausible for a rural location, a gross underestimate for an urban one.) and you know only one person is guilty....

How do you have "probable" cause when the probability for each individual is only 0.1%? That seems pretty heavily on the improbable end of the scale.

[Noscitur a sociis]

Do you think the police need probable cause to interview someone?

[Stephen Lathrop]

I think the police need either probable cause, or a person's consent to be interviewed. Where do you find either one of those in the case of a geofence dragnet?

[Noscitur a sociis]

Your understanding of the law appears to be incorrect: people can be compelled to answer questions from the government, which generally don’t require a showing of probable cause.

Your understanding of the facts of this case is also incorrect: there was probable cause that there would be evidence of the crime in Google’s database, which is how the police were able to get a search warrant for it in the first place.

[Stephen Lathrop]

Yeah. I guess I left tacit my objection to thimble rigging the answers to forthright questions.

[Noscitur a sociis]

I’m not really following your complaint. Bubba Jones, Brett Bellmore, and you are all attempting an argument by analogy that’s based on a fundamental misconception of how what the law governing the hypothetical actually is. I’m providing you with accurate information so that we can hopefully have a more illuminating discussion.

[Brett Bellmore]

Setting aside that I don't understand what he means by "thimble rigging" either; Is it some obscure slang?

We're actually aware that the jurisprudence is as you say. We think it's illegitimately so, given the actual text of the Constitution.

[Ridgeway]

How do you figure? An interview is not a search in any normal sense of the word, and it is not a seizure unless the police prevent you from leaving.

To my mind, the courts have twisted the meaning of the word "search," at least as applied to the individual's asserting their 4th amendment rights, beyond recognition in an attempt to achieve "just" results.

[Noscitur a sociis]

Setting aside that I don’t understand what he means by “thimble rigging” either; Is it some obscure slang?

I had never heard it before either, but according to my warrantless search of google records, it’s another term for shell game.

We’re actually aware that the jurisprudence is as you say. We think it’s illegitimately so, given the actual text of the Constitution.

I don’t think you made that first part clear, but that as it may—what is the text that you think requires probable cause before the police can interview you?

[Armchair]

Let's give a different hypothetical example.

1.) Imagine there's a crime. And imagine there's a video camera that is recording images at the exact location and time of that crime. The police could certainly get a warrant for the record.

2.) Now imagine the same situation. But that video camera uploads its data to "the cloud"...a large database of several billion entries, in a random index entry. That entry is coded by the location and time of the upload. However, in order to find that entry, it needs to be searched for.

3) Now, the police are requesting a search of a database that has several hundred billion entries. Despite knowing exactly what they are looking for, the search is too broad, so won't be allowed.

---Does that make sense---?

[shawn_dude]

If there's a crime at a restaurant at a specific time, the investigators would likely get the reservation list for the people who checked in during that time to start a list of potential suspects. This isn't any different than getting cell phone/tower location data.

[Jason Cavanaugh]

Aside from the obvious difference in magnitude and utter lack of individual suspicion, sure.

[Noscitur a sociis]

How is there any difference in individual suspicion?

[WuzYoungOnceToo]

Second, and much more dramatically, the Fifth Circuit rules that because the database of geofence records is so large, and because the whole database must be scanned through to find matches, the Fourth Amendment does not allow courts to issue warrants to collect those records.

I'm a bit confused by this reasoning. If a warrant is not for the entire database, but for a (presumably relatively small) subset of records from it that match specified criteria, what does the size of the database have to do with 4A? The government is not searching the database to produce the subset of target records. Google (who owns the data) is.

[Noscitur a sociis]

But Google is only doing it because the government is forcing it to, rendering Google a government actor in that context. See Prof. Kerr’s discussion on this point in his work on preservation requests, e.g. https://reason.com/volokh/2024/07/17/internet-preservation-and-the-fourth-amendment-case-updates-part-i/.

[WuzYoungOnceToo]

I think the problem here is the use of the word "search", which means something very different when it comes to retrieving digitally stored data than what the word means in the context of 4A. In the latter, someone is actually looking at (and possibly handling) all of whatever it is that's being "searched" through in order to find what it is that's being looked for. But in the case of the former, someone is simply instructing a computer system to report some small subset of a larger set of data based on a given selection criteria. The computer system's software "searches" for that data, but not in the same sense that a person conducts a physical search. Nobody is ever looking at any of the data that is not ultimately returned by the system.

And again...I fail to see what the size of the database has to do with any of this. The same sort of "search" is required regardless of the number of records involved.

[Brett Bellmore]

The government can't delegate to the subject of the warrant what they can't do themselves. If they haven't got the right to see the inside of the safe, they can't compel you to open it.

[WuzYoungOnceToo]

The government can’t delegate to the subject of the warrant what they can’t do themselves. If they haven’t got the right to see the inside of the safe, they can’t compel you to open it.

But nobody is seeing the inside of the digital safe in question. All that anyone is seeing are the specific contents that are the subject of the warrant.

[Rossami]

Google is seeing the inside of the 'digital safe' in this analogy. And they are only doing so at the direction of the government. That makes them a government agent according to the 5th Circuit (and all logic) and subject to the constraints of the Fourth Amendment as they do so.

The fact that they subsequently filter the results of their search before handing the results off to government employees does not absolve the initial violation.

[WuzYoungOnceToo]

Google is seeing the inside of the ‘digital safe’ in this analogy.

When you say, “Google” is seeing inside, who (in terms of human beings) do you mean? Like I said, nobody is seeing the “inside of the safe” when they query the database using a search criteria. They only see what the query returns, which is the data that was being sought. So in this analogy, it’s as though someone issued a request to the safe itself to spit out a copy of one of its contents without anyone having to open the door and look inside.

[Absaroka]

I'm not sure there is a direct analogy between human and computer searches here.

Suppose the IRS has cause out the wazoo to think WuzYoung is cheating on his taxes. They get a warrant for WuzYoung's bank records and go to WuzYoung's banks.

Bank1 has a row of file cabinets, They go to the 'W' file cabinet, look through the drawer and see files labeled 'Warren', 'Wilma', ..., 'WuzYoung', 'WWWW', ... and pull the 'WuzYoung' file for the IRS.

Bank2 has a row of cabinets, not indexed by name. They start on cabinet 1 and go through every single transaction and pull all the ones that involve 'WuzYoung'.

Bank3 is computerized and says 'show us all the records for WuzYoung', and hand the results of the query to the IRS. The bank hasn't a clue how the software they purchased is storing the data.

TBH, I don't know what I think about all the variations here. My off the cuff reaction is that I'm interested in the end results, not the underlying details. What the computer is doing under the covers seems to me like the Talmudic debates on whether it's OK to push a button in the elevator on the Sabbath, or is it OK to ride an elevator programmed to stop at every floor, or whether you have to take the stairs. Maybe voice commands are OK, but not pushing a button? What if the elevator senses your floor from your RFID key?

Overall, I think focusing on the results makes more sense.

[WuzYoungOnceToo]

My off the cuff reaction is that I’m interested in the end results, not the underlying details.

But the details matter...especially when the court is saying that the size of the database is an important factor. I still haven't gotten an answer as to why that matters at all. They also matter because there's a reason that search warrants specify what exactly the search is to be limited to.

[WuzYoungOnceToo]

The fact that they subsequently filter the results of their search before handing the results off

But they’re not subsequently filtering the results of their search. The results they get back from the “search” has already been filtered by the software they’re using to query the database.

[Rossami]

I think you are wrong on your starting premise. Specifically, where you assert that "users who have opted into having Internet providers retain location history", you incorrectly assume that the opt-in is meaningful. If the opt-in is not truly informed and voluntary, then the "third party doctrine" should not apply and Chatrie was wrongly decided.

But as you say, that's not the primary focus of this article. Re: the particularity arguments, how is 'these hundred people were in the vicinity' "evidence or contraband that is evidence of the crime"? Your analogy from Karo is uncompelling. That was a beeper attached to a vehicle of a person who was already a suspect. It was far less of a fishing expedition than 'let's look up everyone who was inside the geofence'.

I'll also note that the dicta in Carpenter saying that "The Government will be able to use subpoenas to acquire records in the overwhelming majority of investigations" is, well, dicta - and uncompelling to boot. Your general arguments relying on Carpenter assumes the outcome of challenges that weren't made in that case. Carpenter's assumptions can not be automatically determinative once those assumptions are called into question.

Will this threaten the viability of other sweeping internet-based searches? Yes and that is the point! The goal of the Fourth Amendment is not to make government's job easier.

[Noscitur a sociis]

But as you say, that’s not the primary focus of this article. Re: the particularity arguments, how is ‘these hundred people were in the vicinity’ “evidence or contraband that is evidence of the crime”?

That’s where the tailoring to narrow areas and time windows come in. If you grant that a warrant is required is required, then it certainly is possible to imagine one that sweeps too broadly, but it also seems obvious that it can be properly focused in appropriate cases. This warrant, for instance, didn’t show that hundreds of people were in the area: it showed that three were, and two of them were the robbers. (Note too that law enforcement has would have an incentive to tailor the requests even if it wasn’t legally required for precisely the reason you note: getting hundreds of leads isn’t very useful.)

Your general arguments relying on Carpenter assumes the outcome of challenges that weren’t made in that case. Carpenter‘s assumptions can not be automatically determinative once those assumptions are called into question.

The problem isn’t the inconsistency with Carpenter’s assumptions: it’s the inconsistency with Carpenter’s holding—which, you’ll recall, wasn’t that the government couldn’t access this data, but rather that they needed a search warrant to do it. If you accept that (like the Fifth Circuit is supposed to), then it’s hard to see how the search here, which revealed much less information about the defendants, could be off-limits.

[Rossami]

I think you missed my point. Carpenter's holding depended on Carpenter's assumptions which were not challenged or even addressed by either the parties or the court when that decision was decided. Carpenter's holding can not be simply assumed to be determinative when those assumptions are subsequently challenged in a case that properly preserves and briefs those issues.

[Noscitur a sociis]

What assumptions do you have in mind, exactly?

[Commenter_XY]

Part of the problem with particularity getting the physical location small enough, correct? I just want to be sure I am following you correctly.

[Noscitur a sociis]

I’d agree that if a warrant is required, it needs to be limited to information from a sufficiently narrow area (and time). I think that’s more a matter of probable cause (or its lack) than particularity though.

[Vandalia]

The problem is the size of the area to be searched.

You and Kerr are arguing that if a warrant to search a room for a particular firearm is valid, then it necessarily holds that a warrant to search every structure in the entire county for that firearm is also necessarily valid.

The specificity of the thing being searched for is irrelevant; or more precisely it in and of itself does not make a warrant valid. The "field" of the search is the most important factor in determining its validity; assuming all else is proper. Otherwise, you end up being forced to hold that a single warrant authorizing a search of every inch of the country is necessarily valid.

[Noscitur a sociis]

I don’t see how you’re getting this from anything I (or Prof. Kerr) have said. The warrant has to be particular as to the place to be searched, but it is: the place is Google’s records. The location that the warrant is seeking information about is part of the things to be seized. (That also has to be described with particularity of course, but I don’t really see any argument here that it wasn’t.)

[dirc]

Suppose Google did not have to search the records of all 592 million individual accounts for the entire 18 months that geolocation records are retained. Would that change the logic of the court's decision? I don't know how Google organizes their Sensorvault data, but suppose:
- United States location data is grouped in 10x10 mile tiles.
- The location data is grouped in hourly intervals for each tile.

If that is the case, then to search all records within 1 mile of a location in a one hour time interval would require searching at most four tiles and two intervals with those tiles, a total of eight tiles and intervals. That might reduce the number of records searched from 592 million over an 18 month period to a few thousand over a two hour period. Should that change the court's decision?

As a side note, according to Wikipedia (https://en.wikipedia.org/wiki/Sensorvault) Google is changing how it stores geolocation information so that they will no longer be able to respond to geofence warrants.

[shawn_dude]

And, as I mentioned above, a database search doesn't necessarily look into the full record itself but largely relies on indexing information that is derived from but limited and separate from the source record.

[Michael P]

You switched from counting 592 million people to assuming there are only 592 million geolocation records. Most people power on their cell phone during more than one hour, so your arithmetic would significantly undercount the number of records being searched (even if people never moved).

[Reasonable in Florida]

Perhaps the most surprising thing is the panel that issued the well off the mark decision. You might expect it of Ho or other Trump appointees, but this was King, Ho, and Engelhardt.

King, Carter appointed. Ho, Trump and often extreme. Engelhardt: a Bush appointee.

Strange…

[Noscitur a sociis]

I’m not sure that Trump appointees are especially notorious for going out of their way to protect criminal defendants. And Ho’s concurrence certainly seems on brand.

[flag58]

If my Google maps timeline is a good example of the location data, the accuracy sucks.

[JoeFromtheBronx]

I don't know how useful it is to reference a 1980s case involving a beeper to determine the proper rules in this context. The limited scope as compared to the warrant here is glaring.

The reach of this opinion, including not allowing a search even with a warrant, along with the circuit split that arose, does seem to make it cert-worthy at some point.

[Noscitur a sociis]

I don’t know how useful it is to reference a 1980s case involving a beeper to determine the proper rules in this context. The limited scope as compared to the warrant here is glaring.

Can you elaborate? This search seems much less intrusive than a tracking device to me.

[Michael P]

Cell site records will find many more devices than a single car -- there is some minimum average number of devices that make it economical for a cell phone provider to provide service in an area. Unless a cell phone has a better source of precise location (WiFi base station or Bluetooth beacon, GPS receiver turned on with reasonable sky view, etc.) the phone's idea of its location will be poor: when you first open a map app, or when you leave a tunnel, you'll often see a location circle that is a significant fraction of a mile in diameter. That's the rough resolution that a geolocation search will provide, and most courts would not issue a warrant that is general to buildings in (say) a four-block area. You'd need some special case like all the buildings being part of a single facility.

[JoeFromtheBronx]

I'm not sure why you think it is less intrusive.

As to my thinking. The usage of a beeper to track a can is a primitive search device with a limited reach as compared to the breadth of the tool used here. It processes much more information than what is used to track a single container with a beeper.

The use of a tool to "access location information for users who have opted [the opinion questions how much they 'opted'] into having Internet providers retain location history" to me is more "intrusive" in possible scope than a single beeper would be.

[Vandalia]

So under your reasoning, a warrant to search every house and building in the county for a particular firearm would be a valid warrant, since it describes with precision the item to be searched for.

[Davy C]

"and particularly describing the place to be searched, and the persons or things to be seized."

Those are two distinct requirements. A database is not a place. If they want to do this, they need to particularly describe the location of the server the database is on.

[NvEric]

'A database is not a place. '
Exactly !
And, the data contained is not a thing, but rather transitory electrical charges or magnetic fields capable of manipulation and degradation.

These records kept are not of call locations, but pings, as I understand it. There's a strong case for going too far with useless data storage where those inclined to climate change should be aghast at the amount of energy wasted in this useless data storage. Furthermore, the data references the location of an object and not a person. The two should be thought of as being the same; video data also purports to be likewise held in esteem too, but these electronic devices and their attendant records/data are, as above mentioned, transitory electrical charges or magnetic fields and not things of substance. Only one-time-programable, OTP, electronics can be held to certainty and exclusivity for use in court.

No to having geofencing and cameras capturing images. ( except at ATMs ) Otherwise, and I know it won't ever be stopped peacefully, everyone must have an implanted tracking device so that all will "feel" safe from bad things. It's not my future, but it will be yours.

[vaadu]

Turn off location on your phone except when absolutely necessary.

[PoliFights]

Remember Orin Kerr is nothing but a tool for the ruling class. He even argued the illegal FISA search warrants against Trump in 2015-2017 is totally legal.

Even the corrupt DOJ later admitted the FISA warrants are invalid.

[Squirrelloid]

Just because a crime was committed at a particular location at a particular time, why is that enough to create probable cause for a geofence warrant in the first place.

ie, in order for a geofence warrant to even possibly contain ‘evidence of a crime’, the suspect must own, carry, and have turned on a cellphone which reports location data. Wouldn’t probable cause in this kind of case require a showing that the person who committed a crime did in fact own, carry, and etc… a qualifying cellphone? …before the warrant is issued?

(And how is a list of people who were carrying cellphones reporting location data evidence of a crime?)

It sounds like a fishing expedition, because it sounds like ‘we don’t have any suspects, so let’s get the identities of the idiots dumb enough to let their cell phones track them, and make them our suspects’.

[Noscitur a sociis]

Just because a crime was committed at a particular location at a particular time, why is that enough to create probable cause for a geofence warrant in the first place.

ie, in order for a geofence warrant to even possibly contain ‘evidence of a crime’, the suspect must own, carry, and have turned on a cellphone which reports location data. Wouldn’t probable cause in this kind of case require a showing that the person who committed a crime did in fact own, carry, and etc… a qualifying cellphone? …before the warrant is issued?

For all the reasons explained in this opinion and in Carpenter, I think it’s fair to infer a reasonable likelihood that people will be using and carrying phones in most cases, at least absent some reason to think they aren’t, just in light of the realities of modern life. No, there’s not a certainty of it, but probable cause doesn’t require that. But in this case, there was also surveillance video showing the perpetrator using a phone.

(And how is a list of people who were carrying cellphones reporting location data evidence of a crime?)

Evidence that person’s phone was at the scene of the crime is circumstantial evidenxe that they were there, and evidence that they were there is circumstantial evidence that they were involved. It may, of course, not be conclusive evidence. But it’s certainly evidence.

it sounds like ‘we don’t have any suspects, so let’s get the identities of the idiots dumb enough to let their cell phones track them, and make them our suspects’.

Yes, I think that’s basically what their strategy is. And as this case illustrates, it can work!

[Squirrelloid]

“Yes, I think that’s basically what their strategy is. And as this case illustrates, it can work!”

But isn’t that just a fishing expedition? How is that not a general warrant?

I think the video changes the nature of the case. If they have reason to suspect that person on video who is using a cellphone at the time, then they should be able to get a warrant for that specific call. (They have a time and a pretty specific location. It might return a couple hits, but they're looking for a specific call by or to a specific person, and that sounds okay).

I'd distinguish this from looking for a cell phone in an area with nothing so distinguishing except the time and place the crime was committed).

[Absaroka]

Someone is murdered in Apartment 3G between midnight and 1AM. The building entrances are covered by security cameras.

Should the police be able to get a warrant for the security camera footage from, say, 11PM to 1AM?

There is no guarantee the killer is on the tapes - she could have entered before/left after that interval, or landed by helicopter on the roof or whatever. And of course, they'd only catch killers who had voluntarily 'turned on identification services' by failing to wear a mask or wide brimmed hat or whatever.

[Patrick Henry, the 2nd]

This ruling is only bananas if you believe in unlimited government power.

This ruling is entirely great for those of us who understand the Constitution. Sorry governments, can't do a general warrant.

[Stupid Government Tricks]

I'm on your side, but my understanding is that general warrants searched for evidence of any crime, as in searching a warehouse to look for smuggled goods which had not paid tariffs, whereas geofence warrants are looking for evidence of a specific crime, such as if a mythical reliable informant had said that specific goods in the warehouse had been smuggled without paying the tariff.

It's the kind of lawyerly quibble which earns them their reputation. Since everything in the warehouse gets potentially searched either way, it's a distinction without a difference that matters to non-lawyers.