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Wednesday, November 29, 2017

Carpenter – Post-Oral Argument Thoughts

The following guest post is by past guest-Prawf Andrew Ferguson (UDC).

Today, the Supreme Court heard oral arguments on the much awaited Fourth Amendment case of the term – Carpenter v. United States.  Fourth Amendment nerds from all over the country flocked to the Supreme Court like it was a constitutional solar eclipse. 

Carpenter involves the warrantless collection of historic cell phone records for location information covering 127 days.  Suspected of being involved in a series of armed robberies (ironically enough of cell phone stores), police used Timothy Carpenter’s cell phone location data to tie him to the crimes and obtain a conviction.  Carpenter appealed arguing that obtaining this information without a warrant violated his Fourth Amendment rights.

The reason for the buzz of interest is because the case presents a real legal puzzle.  In a world where almost all of our digital devices work through third parties, the idea that law enforcement can simply obtain the data from our smart devices without a warrant means that our modern culture of self-surveillance has also potentially created a governmental surveillance state.  At the same time, the third party records in Carpenter were owned, controlled, and used by the phone companies, raising questions of who owns this data, who controls it, and does sharing it for one purpose also mean sharing it for all other purposes including government investigation? 

Much (almost instant) commentary has already been posted on this case, but two things are clear: first, the stakes for the future of the Fourth Amendment are quite high and demand an answer; and second, no Justice or advocate has a completely coherent answer to how the third party doctrine should apply in the digital age.

As to the stakes – almost any digital device you can imagine connects to third party providers (and creates third party records) in order to make the magic of “smart” devices happen.  In an interconnected world filled with smartphones, smart cars, smart homes, and smart medical devices, ubiquitous communication by email, text, Tweet, or chat, you share your data with private companies.   In a world of data trails, you are a potential police target at all times.  Your smartphone, your smart car, your fitness band provide exact geo-locational clues to your whereabouts.  Your location is being tracked, and police have recognized the utility of this information to prove criminal acts and patterns.  Data trails provide a wealth of clues to past and present criminal activity

As to the debate in the high court, the Supreme Court was, perhaps not surprisingly, divided.  Questions of how to distinguish decades old precedent mixed with questions about new future-oriented technology.  Hypotheticals about modern subpoena power mixed with queries about the Writs of Assistance.  John Adams got a shout out.  So did Stephen Henderson’s idea of a Fourth Amendment time machine.  So did the empiricists’ amicus brief.  Again, for Fourth Amendment nerds it was a party. 

At least from the questions at oral argument, it can be intuited that some Justices wish to rethink the existing third party records doctrine, and others wish to see how to make it fit a digital age.  (As a disclosure, I helped author one of the amicus briefs on behalf of Mr. Carpenter).  Theories abounded, with no clear resolution of how the Justices would decide. 

But one question – signaling perhaps a new way of thinking about the Fourth Amendment – seemed to trouble at least a few members of the Court – namely what rights (property based or otherwise) do the consumers of smart devices have over their own data.  This is a huge question in the digital age.  How does the Fourth Amendment protect smart data?  How do we conceptualize who owns or controls the location data coming from Carpenter’s cell phone?  

Here is how Justice Gorsuch framed the question to Carpenter’s lawyer Nathan Wessler of the ACLU:

JUSTICE GORSUCH: Mr. Wessler, I'm sorry, one quick question. Focusing on the property-based approach, putting aside reasonable expectation for just a moment, what do we know about what state law would say about this information? So say -- say a thief broke into T Mobile, stole this information and sought to make economic value of it. Would you have a conversion -- would your client have a conversion claim, for example, under state law? Have you explored that at all?

Similar questions were put to the government’s advocate, Michael Dreeben:

JUSTICE GORSUCH: Mr. Dreeben, I'd like to -- I'd like to drill down on that and return to Justice Kagan's question. You know, the facts here wind up looking a lot like Jones.

One thing Jones taught us is -- and reminded us, really, is that the property-based approach to privacy also has to be considered, not just the reasonable expectation approach.

So, if we put aside the reasonable expectation approach for just a moment, Katz, Miller, Smith, and ask what is the property right here, let's say there is a property right. Let's say I have a property right in the conversion case I posited with your colleague. So that if someone were to steal my location information from T-Mobile I'd have a conversion claim, for example, against them for the economic value that was stolen.

Wouldn't that, therefore, be a search of my paper or effect under the property-based approach approved and reminded us in Jones?

            The question likely arises from a law review article written by William Baude and James Stern in the Harvard Law Review called The Positive Law Model of the Fourth Amendment and in Richard Re’s response essay, The Positive law Floor.  Both articles were cited in Carpenter’s brief and apparently caught the attention of the Court.  But, as anyone who has read those thoughtful pieces knows, positive law when it comes to the Fourth Amendment gets confusing and contested pretty quickly in practice.  It is not that the Positive Law model doesn’t offer some helpful ways to conceptualize the possible future rules, but it is hard to operationalize because positive law is messy. 

So, in the spirit of the ongoing debate, I offer my own thoughts to the intuition that Justice Gorsuch was reaching for – that there is some property-like element to our smart data – but with a different conceptual hook.  

My argument is not about positive law, but about the ownership/security interests we have in the data we create.  Smart data (including location data) is partially ours, and because it comes from our effects, we can claim some control over it.  The argument turns on the simple principle that the Fourth Amendment protects not simply the physical integrity of “persons, papers, homes, and effects” but also the information that comes from those constitutional derived sources (which would include Timothy Carpenter’s cell phone – as an effect – and its smart data).  As I wrote in The “Smart” Fourth Amendment:

The Fourth Amendment--at its core--protects “informational security” …. Underlying the protection of persons, papers, homes, and effects and behind the expectation of privacy lies a desire to guard personal information from government intrusion.

In other words, it is not the corporal person, alone, that deserves protection, but also the information about the person. It is not the sheaf of papers, but the revealing personal details in those words that matter. It is not the physical home that is as important as what happens in the home. …

In this longer work on how the Fourth Amendment should adapt to new “smart” technologies, I developed the idea of “informational security” the principle of why the Fourth Amendment should protect smart data, again similar to Justice Gorsuch’s intuition that there is some property/security right to control the locational information created by individuals through the use of smartphones.  [In the following excerpt from the article, I deleted the footnotes for easier reading.]


[I]nformational security is not an abstract concept, but arises from those particular constitutionally referenced sources. The Fourth Amendment secures someone, something, or somewhere. Information obtained from a constitutionally recognized source--effects, houses, persons, papers--gains derivative protection due to the source of the information. Focusing attention on a derivative constitutional source provides a useful and relatively easy guidepost to identify which types of information deserve constitutional protection.

Such derivative protection also covers information at some remove from the actual constitutionally protected interest. Charlie Katz's voice exited the closed glass door and was captured by the microphone taped on top of the phone booth. Antoine Jones's travel coordinates left the car and was captured by satellite technology. David Riley's smartphone communications data existed both on the phone and outside of it (in the cloud). Yet, the protections of the Constitution carried to these intangible, invisible, separate pieces of personal information. The constitutional protections of persons, houses, papers, and effects might, thus, be better characterized as protections of the information emanating from those constitutionally protected interests.


As laid out in more detail in the article, one can trace through the history of the Fourth Amendment and see this emphasis on protecting informational details arising from constitutionally protected sources (effects, homes, persons, papers).  For questions about whether we have any property rights in our own smart data, this can be an important consideration. 

            For example, in terms of effects:

Central to the protection granted effects has been securing personal information about those effects. The sparse Founding Era literature suggests a focus on protecting objects which revealed something about the owner--religion, culture, status, or family associations. Searching and seizing a colonist's religious objects was not offensive simply because it interfered with property rights, but because searching revealed personal information about family and faith. Rummaging through bedroom drawers was not solely about the inviolate nature of property but, as the early history suggested, also about revealing information that might be contained in those drawers. Interpreted one way, the protection of effects has largely been the protection of what the personal effects revealed or contained.

Similarly, while Justice Scalia attempted to ground his Jones argument in property rights, the harm of affixing the GPS device was not in any real sense to physical property (the car was undamaged). The real harm was exposing the revealing personal data about the effect (car). Placing the device on the car might have been a seizure, but what made it a search was collecting the locational data intercepted by police (the “use of that device to monitor the vehicle's movements”). The “use” in that case was the capturing of data trails via satellite transmissions communicated by cell phone to a government computer. By using the car to track its owner, the government invaded the informational security of the effect. Justice Scalia's Jones analysis requires both parts--trespass plus use--and as Justice Alito argues in his concurrence, neither alone should constitute a search under Scalia's reasoning. In holding that this interception/collection was a Fourth Amendment search, Justice Scalia implicitly acknowledged the centrality of informational security. What mattered was securing the information coming from the effect, not just securing the effect itself.

The concurring Justices in Jones also focused on the personal information revealed from the GPS device. The reason a twenty-eight-day tracking of locational data became a search rested solely on the informational exposure that resulted. Such collection of personal data points (touching on associational, health, and other private travels) became of constitutional significance when the data trails could be revealing of private, personal actions. The expectation of privacy was not about expectations from the effect (the car) itself, but the information to be inferred about the travels of the car. This personal information essentially radiating off the car is what created the constitutional harm.

The article goes on to discuss the other constitutionally protected terms and the quirks and problems with the theory of informational security, but at its core the article offers a way to get to a property-oriented approach to data protection without diving into positive law.  (Although, candidly, there are 84 pages of my article not excerpted that add a whole host of complexity to it). 

So, if the Supreme Court is looking for a reason to protect smart data under the Fourth Amendment, it offers a starting point for debate.  And, the best thing about the Carpenter argument day was that for one shining moment, everyone was focused on thinking about the Fourth Amendment and how it should apply to the digital age.  Can’t wait for the decision. 

Posted by Howard Wasserman on November 29, 2017 at 06:41 PM in Constitutional thoughts, Criminal Law, Law and Politics | Permalink


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Posted by: aadila | Jan 29, 2018 7:16:53 AM

Asher writes, "Leaving aside that it's nonsensical to even talk about an expectation of privacy in the fact that one was at a Radio Shack at a particular date and time,"

But why should we leave it aside? I don't take it as self-evident that a person loses all expectation of privacy the moment they walk out the door in a "public" space. We have been trained/conditioned to accept that is the case but there isn't anything natural about it: it just the way we have organized our society. A really great book on this topic is "The City and The City" by China Melville. He explores what happens in a society where it is perfectly sensible to afford a person an expectation of privacy the moment they walk out the door into the "public arena". In the end, Melville probably agree with your position but his fictional exploration of the topic makes clear that the topic is a lot more complex than you give it credit for.

Posted by: Daniel | Dec 1, 2017 7:19:55 PM


Would it change your answer if the phone "pinged" a tower not only when you actively made/received a call with the phone, but also when you didn't do anything yourself - say, it pinged a tower when you received a text message (whether you chose to be notified about that incoming message, or because the text messaging app was operating in the background while your phone sat in your purse/backpack), or it pinged a tower all by itself because your service provider regularly checks in on the phone to see if it's on and where it is?

That is, is there a reason to limit the data available to law enforcement without a warrant to data generated while you actively operated the phone, or should the rule also include location data generated passively when the phone was sitting in your pocket?

The location data during a call is easier to justify under an expectation of privacy framework (mosaic theory aside), but I find it much harder to square the "every tower ping" rule with any sense of a reasonable expectation of privacy that doesn't equate protectable privacy with absolute secrecy.

Posted by: Kevin Lapp | Dec 1, 2017 11:33:07 AM

The point of the GPS case is that the government doesn't have a right to stalk us (without a warrant). Just because we're out in public doesn't give undercover cops the right to follow us everywhere we go (without a warrant). Cell-site data effectively tells the government where we are at all times; that's the exact type of information the fourth amendment (and Griswold's privacy right) were meant to privatize. We have a right to move without being constantly tracked--otherwise Roe's right to privacy means nothing more than the right to an abortion.

Posted by: Jane R | Dec 1, 2017 6:49:59 AM

Asher, the location of your property is a characteristic of the property. Whether your pen is blue or black is also a characteristic of the pen. The government might go into a stationery store you and ask what color pens you buy - but that's neither here nor there in considering whether the government can more directly discover the color of the pen. If you write something - say a check - and give it to someone, the government may then discover the color. However, directly determining the color of your pen in your pocket - or whether it is in your pocket or at your home - should typically require a warrant. There is a good argument that Kyllo was an easy case that should have been decided the other way. Yet I think the Court was correct there in not hitching 4th Amendment protection to the vagaries of technology. And the problem is that if the Court does start doing that, the protections of the 4th Amendment will largely evaporate in face of new technology.

Posted by: Joseph | Dec 1, 2017 2:14:13 AM

I find this a stupefyingly easy case. A person places a call on his cellphone service provider's network. That provider is in the business of putting his calls through. They keep records of the times at which they provide the service of connecting their customer's phone calls, records of whom they put the calls through to, and records of the points at their network from which they provide this service. The government asks the provider for the records it creates of the service it provides to its customers because that information incidentally happens to be good at placing someone's location, assuming that that person talks on the phone much. (If he doesn't, it's useless.) It reveals that the company connected his calls at points and times coincident with various robberies. The defendant wants to suppress this information because it reveals too much about his location in such places as the parking lot of the Radio Shack he robbed.

Leaving aside that it's nonsensical to even talk about an expectation of privacy in the fact that one was at a Radio Shack at a particular date and time, it's equally risible to talk about an expectation of privacy in provider-created records of the service that the provider rendered for him. Suppose the robber had spent four months casing a difficult bank job in a small town that only has one diner. The police would logically ask the diner if they had ever served him, and when. Failing recollections, they would next ask for their records of credit card transactions. From these records, they might find that the robber ate at the diner daily over a four-month period. It is fatuous, I hope people would agree, to suggest that a customer at a diner has an expectation of privacy in the diner's records of his purchases of their food, or his waitress's recollections of it ("why yes, Officer, he came in every day!"), yet just the same information would be obtained about the robber's whereabouts over a lengthy period that the police got in Carpenter. What's so special about cell-site records, their relative efficacy? There are probably people who go to various Starbucks locations more times in a day than they make or receive a call on their cellphone. A dump of the Starbucks stores from which a suspect used his Starbucks card over a four-month period could be just as effective as placing those people's location as cell-site records were at placing Carpenter, so what are we going to do, say that Starbucks is different from diners because there are more Starbucks locations to collect data from?

As for this business of information radiating from my effects, I can't see. My pen is an effect; I write things with it. Some of them are personal, I guess. I'm sure you won't tell me I have an expectation of privacy in the personal information radiating from my pen, so long as that information irradiates into a third party's hands, like a bank or the holder of a check.

Posted by: Asher Steinberg | Nov 30, 2017 6:49:26 PM

He who wants , can read that case , concerning search of data in cell phone as mentioned , here :



Posted by: El roam | Nov 30, 2017 6:48:36 PM

Just as you simplify the matter of the property interest at stake, I think the illusion of complexity can be dispelled with regard to the third party doctrine as it applies to this case.

We can imagine an alternate history of 4th Amendment jurisprudence regarding telephones. There was early prevalent use of party lines where any neighbor might be listening (and people knew it); there was the basic fact that voices were transmitted over a third party's lines where switchboard operators were routing the calls, and also potentially listening in. It ultimately didn't matter whether the callers knew (actually or constructively) someone was, or could, be listening in and it didn't matter whether the state of affairs was part and parcel of the technology. The Court has held that there is a 4th Amendment right at stake, based essentially on an expectation of privacy. We can imagine if the Court went the other way and decided instead that voices transmitted through a phone company's lines didn't merit protection.

The Justices touched on this point only briefly and barely discussed the voluntariness required under the third party doctrine. Talking over a third party's phonelines, maybe with a neighbor or switchboard operator listening, was a voluntary act, to be sure. But the person did not intend to divulge the content of the conversations to switchboard operators and neighbors even if they typically recognized it was possible.

There is a certain deliberation required under the third party doctrine for each act of communicating with a third party. Whether pressing telephone buttons for each call or engaging in discrete (not discreet) banking transactions, one is deliberately giving information to a third party. It was not that obtaining a phoneline gave rights to Ma Bell to information transmitted over its services nor that opening a bank account permitted a bank to any information. It was each discrete call (the typing of the numbers) and banking transactions that the person deliberately conducted, thereby voluntarily conveying to the third party.

In Carpenter, the government pushes the idea that merely obtaining a cellphone means you've surrendered rights up front, with no further act of divulgence needed to be carried out by the owner of the cellphone.

The expectations game is complicated by new developments. It is reported that the newest iphone doesn't let you turn off wifi and bluetooth even though it looks like you've turned it off. Privacy rights for data transmitted over wifi is still something of an open question. And it may be in the future that you've turned off your cell reception (or so you're led to believe) but it keep pinging towers anyway. According to the government, the cellphone contract means you have no 4th Amendment rights to the location data of your cellphone in any event.

Kyllo and Jones were difficult cases, in a sense, but in hindsight they were perfectly consonant with traditional notions of privacy and protection of our property. Hopefully the Court continues that trend in Carpenter. This case isn't so complicated as both parties have made it out to be.

Posted by: Joseph | Nov 30, 2017 6:01:41 PM

Thanks Andrew , I shall look forward for reading such interesting piece of book . Concerning third party data holder , I didn't have much time , just should be noticed , that one must distinguish between three phases generally speaking :
Data folded and stored within private device ( Smart phone for example ) than it is owned by the person . While on air transmitted , doesn't belong to no one , and , stored at the data base of the communication provider ( then , has to do , with the nature of the contract between the provider and the person/ user , on one hand , on the other , statutory obligations to store it for the use of governmental agencies ) . Whatsoever , for the purpose of fourth amendment , really redundant …. This is because of the fact , that the main issue , shall always be , the relevancy and legality of the intrusion , so whether private , public , hybrid , not that much critical .However , the real issue , is how to search , and separate relevant data , without being exposed to huge intimate data , not relevant to the search . But really complicated ….

Posted by: El roam | Nov 30, 2017 6:35:49 AM

El roam:

Thank you. I literally just wrote a book about how big data technologies are distorting policing and the Fourth Amendment... https://www.kirkusreviews.com/book-reviews/andrew-guthrie-ferguson/the-rise-of-big-data-policing/

Worth debating these issues and points. Thanks.

Posted by: Andrew Ferguson | Nov 29, 2017 9:52:24 PM

Thanks for that interesting post , many issues and not less complications , yet , one should pay attention also , to that doctrine of " naked eye " or " plain view " in digital ages . This is because the simple fact , that in such digital age , " quantity " is quickly rendered " quality " , and since governmental agencies , can without considerable efforts and resources , continuously and conveniently monitoring persons from remote places , then , the doctrine of expectation for privacy ( in plain view places or public domains ) is turned on its head in fact . Here I quote from : Michael A. Cunningham V. New York state department of Labor :

" In Weaver, we explained that GPS tracking is more intrusive than simply following a car, and that GPS surveillance is not analogous to visual surveillance for the purposes of constitutional analysis (see Weaver, 12 NY3d at 441).GPS is not a mere enhancement of human sensory capacity, it facilitates a new technological perception of the world in which the situation of any object may be followed and exhaustively recorded over, in most cases, a practically unlimited period.The potential for a similar capture of information or ’seeing’ by law enforcement would require, at a minimum, millions of additional police officers and cameras on every street lamp” (id. at 441). It took ”little imagination” for us to conjure the types of indisputably private” information that would be ”disclosed in the data” from a GPS device planted on a person’s vehicle:T]rips to the psychiatrist, the plastic surgeon, the abortion clinic, the AIDS treatment center, the strip club, the criminal defense attorney, the by-the-hour motel, the union meeting, the mosque, synagogue or church, the gay bar and on and on. What the technology yields and records with breathtaking quality and quantity is a highly detailed profile, not simply of where we go, but by easy inference, of our associations — political, religious, amicable and amorous, to name only a few — and of the pattern of our professional and avocational pursuits” (id. at 441-442; see Jones, 132 S Ct at 955 [citing Weaver for the proposition that ”GPS monitoring generates a precise, comprehensive record of a person’s public movements that reflects a wealth of detail about [his or] her familial, political, professional, religious, and sexual associations”]).Recognizing that, "[w]ithout judicial oversight, the use of [GPS] devices presents a significant and, to our minds, unacceptable risk of abuse” (Weaver, 12 NY3d at 447), we held that ”[u]nder our State Constitution . . . the installation and use of a GPS device to monitor an individual’s whereabouts requires a warrant supported by probable cause” (id.). "

End of quotations :

So , if dealing with smart phones and alike electronic devices , one must shift to another perception or expectation for privacy . Finally , one should not forget , the fourth amendment , is also about perception of citizens ( " be secured " be ,that means also to feel so , feel secured , while no more so , in plain view or public domains it seems ) .

One can reach the case cited , in the supreme court of New York here ( appellate division , not from there cited ) :



Posted by: El roam | Nov 29, 2017 9:22:22 PM


I don’t disagree. While I hope in the current environment this Court addresses the Fourth Amendment question before it, I have also advocated for more robust local, democratic engagement. I posted this article Monday about the need for local surveillance summits. https://injusticetoday.com/why-we-need-local-surveillance-summits-95af6b59ba7a

Posted by: Andrew Ferguson | Nov 29, 2017 9:21:01 PM

"and second, no Justice or advocate has a completely coherent answer to how the third party doctrine should apply in the digital age."

Correct. And in the final analysis isn't what the political process is for? The justices know no more than anyone else on these issues, as Breyer made note to mention. I don't see how asking SCOTUS to resolve these types of issue on a case by case basis is reflective of a healthy democratic society.

I consider myself something of a 4A nerd and I am conversant in the technological aspects as well (encryption, etc.) and I don't have the foggiest idea how to balance the rights of privacy and law enforcement in the digital age. In my view the ultimate resolution to these types questions are not found in asking about what is "morally right" or how to "balance power" or what legal framework to use for defining "reasonable". The ultimate resolution to these questions lies in who we want to be as a people in the future and what kind of organized society we want to take credit (or blame) for making. Courts are not designed nor should they be tasked with the ability to answer those types of questions all by themselves.

I respect the Framers and I respect the role the courts play in our Constitutional framework. Yet at some point in time with the enormous changes that have gone on in the last 200 years tasking the court to continuously redefine what is reasonable in light of changing technology without any input from the democratic process makes the people a spectator rather than an agent in their own future.

Posted by: James | Nov 29, 2017 9:08:21 PM

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