United States: My Data, Your Data? The US Supreme Court Puzzles Over The Fundamental Rights Status Of Third-Party Personal Data

Last Updated: July 17 2018
Article by Gordon Downie

In a world in which personal data is increasingly held, and indeed generated by, third parties (social media firms, financial institutions and utilities), it is becoming increasingly important to establish what our legal relationship to that third-party controlled personal data (TCPD) actually is, not only in terms of data protection legislation, but also at the level of fundamental privacy rights.

In a 5/4 split decision last month in the case of Carpenter v US, the US Supreme Court addressed the question of whether cell-site location information (CSLI) which disclosed a suspected criminal's whereabouts was protected from discovery without a warrant under the Fourth Amendment to the US Constitution which protects, "[t]he right of the people to be secure in their persons, houses, papers, and effects, against unreasonable searches and seizures".

Carpenter – the background

Mr Carpenter had been convicted of participation in various robberies with the assistance of evidence of his whereabouts on the day of the robberies which had been subpoenaed from mobile phone firms. The firms had handed over CSLI generated by Mr Carpenter's mobile phone on the day in question and held by the mobile phone firms.

The Chief Justice, writing for the majority, described the nature and significance of CSLI as follows:

"Each time the phone connects to a cell site, it generates a time-stamped record known as cell-site location information (CSLI). The precision of this information depends on the size of the geographic area covered by the cell site. The greater the concentration of cell sites, the smaller the coverage area. As data usage from cell phones has increased, wireless carriers have installed more cell sites to handle the traffic. That has led to increasingly compact coverage areas, especially in urban areas.

Wireless carriers collect and store CSLI for their own business purposes, including finding weak spots in their network and applying "roaming" charges when another carrier routes data through their cell sites. In addition, wireless carriers often sell aggregated location records to data brokers, without individual identifying information of the sort at issue here. While carriers have long retained CSLI for the start and end of incoming calls, in recent years phone companies have also collected location information from the transmission of text messages and routine data connections. Accordingly, modern cell phones generate increasingly vast amounts of increasingly precise CSLI".

The 'Katz' and 'Miller' tension

In tackling the question of whether Mr Carpenter enjoyed Fourth Amendment rights over the CLSI disclosing his movements, the Court was confronted with a tension in its own prior case law.

First, the Court had already established many years ago in Katz v US that Fourth Amendment protection applies to people and not places. Thus, it is not tied to the notion of common-law trespass, i.e., the physical intrusion into a constitutionally protected area, but rather to the 'private sphere', or in other words to anything in respect of which a person has a 'reasonable expectation of privacy'.

Second, however, in a series of cases the Court had also, as the Chief Justice put it, "drawn a line between what a person keeps to himself and what he shares with others", or put another way, the Court had found that a person has no legitimate expectation of privacy in TCPD, or "information he voluntarily turns over to third parties".

One of the leading decisions in that series was the case of US v Miller. While investigating Miller for tax evasion, the Government subpoenaed his banks, seeking several months of canceled cheques, deposit slips, and monthly statements. The Court rejected a Fourth Amendment challenge to the records collection since: Miller could assert neither ownership nor possession of the documents (they were business records of the banks); and the cheques were not confidential communications but negotiable instruments to be used in commercial transactions and the bank statements contained information exposed to bank employees in the ordinary course of business. The Court thus concluded that Miller had taken the risk, in revealing his affairs to another, that the information would be conveyed by that person to the Government.

The majority view – 'Miller' distinguished

The majority ruled that the CSLI relating to Mr Carpenter's whereabouts did benefit from Fourth Amendment protection. In his opinion for the majority, the Chief Justice sought to distinguish the TCPD (i.e., records of banking transactions) in Miller from the CSLI both in terms of the revealing and indiscriminate nature of the CSLI and the 'involuntary' way it was collected.

As he put it:

"The Government's position fails to contend with the seismic shifts in digital technology that made possible the tracking of not only Carpenter's location but also everyone else's, not for a short period but for years and years. [...] There is a world of difference between the limited types of personal information addressed in [...] Miller and the exhaustive chronicle of location information casually collected by wireless carriers today".

"Cell phone location information is not truly "shared" as one normally understands the term. In the first place, cell phones and the services they provide are "such a pervasive and insistent part of daily life" that carrying one is indispensable to participation in modern society".

A glimpse into a post-'Miller' future?

Whilst the dissenting four Justices took differing views of the application of Miller in the present case, three of them were satisfied that the CSLI did not merit Fourth Amendment protection given that it was not owned or controlled by Mr Carpenter.

Kennedy J, who announced his retiral shortly after the case was decided, was particularly dismissive of the majority's attempt to distinguish Miller by reference to the revealing nature of the CSLI. As he put it:

"[C]ell-site records, as already discussed, disclose a person's location only in a general area. The records at issue here, for example, revealed Carpenter's location within an area covering between around a dozen and several hundred city blocks. Areas of this scale might encompass bridal stores and Bass Pro Shops, gay bars and straight ones, a Methodist church and the local mosque. These records could not reveal where Carpenter lives and works, much less his "familial, political, professional, religious, and sexual associations". [...] By contrast, financial records and telephone records do " 'revea[l] . . . personal affairs, opinions, habits and associations.' [...]. What persons purchase and to whom they talk might disclose how much money they make; the political and religious organizations to which they donate; whether they have visited a psychiatrist, plastic surgeon, abortion clinic, or AIDS treatment center; whether they go to gay bars or straight ones; and who are their closest friends and family members. The troves of intimate information the Government can and does obtain using financial records and telephone records dwarfs what can be gathered from cell-site records".

By contrast, the dissenting opinion of Gorsuch J (the first of perhaps two Trump appointees to the Supreme Court) expresses deep scepticism of the Miller line of cases and opens up the possibility of not simply distinguishing but rather overruling Miller in the not too distant future and establishing a fresh Fourth Amendment approach to TCPD.

In his admirably frank opinion, Gorsuch J offers the following thought:

"What's left of the Fourth Amendment? Today we use the Internet to do most everything. Smartphones make it easy to keep a calendar, correspond with friends, make calls, conduct banking, and even watch the game. Countless Internet companies maintain records about us and, increasingly, for us. Even our most private documents— those that, in other eras, we would have locked safely in a desk drawer or destroyed—now reside on third party servers.

[...] Miller teach[es] that the police can review all of this material, on the theory that no one reasonably expects any of it will be kept private. But no one believes that, if they ever did".

Fourth Amendment Protection

Instead, Gorsuch J calls for the application of Fourth Amendment protection to TCPD in circumstances in which, in line with familiar private law concepts, the relevant third party should be regarded as occupying a position of trust. As he puts it:

"Ever hand a private document to a friend to be returned? Toss your keys to a valet at a restaurant? Ask your neighbor to look after your dog while you travel? You would not expect the friend to share the document with others; the valet to lend your car to his buddy; or the neighbor to put Fido up for adoption. Entrusting your stuff to others is a bailment".

In light of Carpenter, TCPD – and not simply the form of TCPD captured in the form of CSLI – looks set to enjoy more generous Fourth Amendment protection than was previously thought under Miller, even if (although this now seems a distinct possibility) the Supreme Court declines to undertake a more 'root and branch' reappraisal of the status of the Fourth Amendment status of TCPD.

The content of this article is intended to provide a general guide to the subject matter. Specialist advice should be sought about your specific circumstances.

To print this article, all you need is to be registered on Mondaq.com.

Click to Login as an existing user or Register so you can print this article.

Similar Articles
Relevancy Powered by MondaqAI
In association with
Related Topics
Similar Articles
Relevancy Powered by MondaqAI
Related Articles
Related Video
Up-coming Events Search
Font Size:
Mondaq on Twitter
Mondaq Free Registration
Gain access to Mondaq global archive of over 375,000 articles covering 200 countries with a personalised News Alert and automatic login on this device.
Mondaq News Alert (some suggested topics and region)
Select Topics
Registration (please scroll down to set your data preferences)

Mondaq Ltd requires you to register and provide information that personally identifies you, including your content preferences, for three primary purposes (full details of Mondaq’s use of your personal data can be found in our Privacy and Cookies Notice):

  • To allow you to personalize the Mondaq websites you are visiting to show content ("Content") relevant to your interests.
  • To enable features such as password reminder, news alerts, email a colleague, and linking from Mondaq (and its affiliate sites) to your website.
  • To produce demographic feedback for our content providers ("Contributors") who contribute Content for free for your use.

Mondaq hopes that our registered users will support us in maintaining our free to view business model by consenting to our use of your personal data as described below.

Mondaq has a "free to view" business model. Our services are paid for by Contributors in exchange for Mondaq providing them with access to information about who accesses their content. Once personal data is transferred to our Contributors they become a data controller of this personal data. They use it to measure the response that their articles are receiving, as a form of market research. They may also use it to provide Mondaq users with information about their products and services.

Details of each Contributor to which your personal data will be transferred is clearly stated within the Content that you access. For full details of how this Contributor will use your personal data, you should review the Contributor’s own Privacy Notice.

Please indicate your preference below:

Yes, I am happy to support Mondaq in maintaining its free to view business model by agreeing to allow Mondaq to share my personal data with Contributors whose Content I access
No, I do not want Mondaq to share my personal data with Contributors

Also please let us know whether you are happy to receive communications promoting products and services offered by Mondaq:

Yes, I am happy to received promotional communications from Mondaq
No, please do not send me promotional communications from Mondaq
Terms & Conditions

Mondaq.com (the Website) is owned and managed by Mondaq Ltd (Mondaq). Mondaq grants you a non-exclusive, revocable licence to access the Website and associated services, such as the Mondaq News Alerts (Services), subject to and in consideration of your compliance with the following terms and conditions of use (Terms). Your use of the Website and/or Services constitutes your agreement to the Terms. Mondaq may terminate your use of the Website and Services if you are in breach of these Terms or if Mondaq decides to terminate the licence granted hereunder for any reason whatsoever.

Use of www.mondaq.com

To Use Mondaq.com you must be: eighteen (18) years old or over; legally capable of entering into binding contracts; and not in any way prohibited by the applicable law to enter into these Terms in the jurisdiction which you are currently located.

You may use the Website as an unregistered user, however, you are required to register as a user if you wish to read the full text of the Content or to receive the Services.

You may not modify, publish, transmit, transfer or sell, reproduce, create derivative works from, distribute, perform, link, display, or in any way exploit any of the Content, in whole or in part, except as expressly permitted in these Terms or with the prior written consent of Mondaq. You may not use electronic or other means to extract details or information from the Content. Nor shall you extract information about users or Contributors in order to offer them any services or products.

In your use of the Website and/or Services you shall: comply with all applicable laws, regulations, directives and legislations which apply to your Use of the Website and/or Services in whatever country you are physically located including without limitation any and all consumer law, export control laws and regulations; provide to us true, correct and accurate information and promptly inform us in the event that any information that you have provided to us changes or becomes inaccurate; notify Mondaq immediately of any circumstances where you have reason to believe that any Intellectual Property Rights or any other rights of any third party may have been infringed; co-operate with reasonable security or other checks or requests for information made by Mondaq from time to time; and at all times be fully liable for the breach of any of these Terms by a third party using your login details to access the Website and/or Services

however, you shall not: do anything likely to impair, interfere with or damage or cause harm or distress to any persons, or the network; do anything that will infringe any Intellectual Property Rights or other rights of Mondaq or any third party; or use the Website, Services and/or Content otherwise than in accordance with these Terms; use any trade marks or service marks of Mondaq or the Contributors, or do anything which may be seen to take unfair advantage of the reputation and goodwill of Mondaq or the Contributors, or the Website, Services and/or Content.

Mondaq reserves the right, in its sole discretion, to take any action that it deems necessary and appropriate in the event it considers that there is a breach or threatened breach of the Terms.

Mondaq’s Rights and Obligations

Unless otherwise expressly set out to the contrary, nothing in these Terms shall serve to transfer from Mondaq to you, any Intellectual Property Rights owned by and/or licensed to Mondaq and all rights, title and interest in and to such Intellectual Property Rights will remain exclusively with Mondaq and/or its licensors.

Mondaq shall use its reasonable endeavours to make the Website and Services available to you at all times, but we cannot guarantee an uninterrupted and fault free service.

Mondaq reserves the right to make changes to the services and/or the Website or part thereof, from time to time, and we may add, remove, modify and/or vary any elements of features and functionalities of the Website or the services.

Mondaq also reserves the right from time to time to monitor your Use of the Website and/or services.


The Content is general information only. It is not intended to constitute legal advice or seek to be the complete and comprehensive statement of the law, nor is it intended to address your specific requirements or provide advice on which reliance should be placed. Mondaq and/or its Contributors and other suppliers make no representations about the suitability of the information contained in the Content for any purpose. All Content provided "as is" without warranty of any kind. Mondaq and/or its Contributors and other suppliers hereby exclude and disclaim all representations, warranties or guarantees with regard to the Content, including all implied warranties and conditions of merchantability, fitness for a particular purpose, title and non-infringement. To the maximum extent permitted by law, Mondaq expressly excludes all representations, warranties, obligations, and liabilities arising out of or in connection with all Content. In no event shall Mondaq and/or its respective suppliers be liable for any special, indirect or consequential damages or any damages whatsoever resulting from loss of use, data or profits, whether in an action of contract, negligence or other tortious action, arising out of or in connection with the use of the Content or performance of Mondaq’s Services.


Mondaq may alter or amend these Terms by amending them on the Website. By continuing to Use the Services and/or the Website after such amendment, you will be deemed to have accepted any amendment to these Terms.

These Terms shall be governed by and construed in accordance with the laws of England and Wales and you irrevocably submit to the exclusive jurisdiction of the courts of England and Wales to settle any dispute which may arise out of or in connection with these Terms. If you live outside the United Kingdom, English law shall apply only to the extent that English law shall not deprive you of any legal protection accorded in accordance with the law of the place where you are habitually resident ("Local Law"). In the event English law deprives you of any legal protection which is accorded to you under Local Law, then these terms shall be governed by Local Law and any dispute or claim arising out of or in connection with these Terms shall be subject to the non-exclusive jurisdiction of the courts where you are habitually resident.

You may print and keep a copy of these Terms, which form the entire agreement between you and Mondaq and supersede any other communications or advertising in respect of the Service and/or the Website.

No delay in exercising or non-exercise by you and/or Mondaq of any of its rights under or in connection with these Terms shall operate as a waiver or release of each of your or Mondaq’s right. Rather, any such waiver or release must be specifically granted in writing signed by the party granting it.

If any part of these Terms is held unenforceable, that part shall be enforced to the maximum extent permissible so as to give effect to the intent of the parties, and the Terms shall continue in full force and effect.

Mondaq shall not incur any liability to you on account of any loss or damage resulting from any delay or failure to perform all or any part of these Terms if such delay or failure is caused, in whole or in part, by events, occurrences, or causes beyond the control of Mondaq. Such events, occurrences or causes will include, without limitation, acts of God, strikes, lockouts, server and network failure, riots, acts of war, earthquakes, fire and explosions.

By clicking Register you state you have read and agree to our Terms and Conditions