Skip Navigation

Supreme Court Strengthens Digital Privacy

The Supreme Court decided that historical location information from your cell phone is private and that if the government wants to see where you and your cell phone have been, then they need a warrant. It’s a big win for privacy advocates and will likely have important consequences for cases across the country.

June 22, 2018

Today, the Supreme Court decided that histor­ical loca­tion inform­a­tion from your cell phone is private and that if the govern­ment wants to see where you and your cell phone have been, then they need a warrant. It’s a big win for privacy advoc­ates and will likely have import­ant consequences for cases across the coun­try.

Here’s what you need to know about today’s land­mark privacy case, Carpenter v. United States:

1. What does this mean for me?

Whenever you move around with a cell phone in your pocket or bag, your loca­tion is sent regu­larly to the phone company, which stores it. This cell phone loca­tion inform­a­tion is now protec­ted by the Fourth Amend­ment against warrant­less search and seizure.

Before today, the govern­ment could obtain that inform­a­tion from your phone company to retro­spect­ively trace your move­ments over a period of time, without obtain­ing a warrant. Where tech­no­logy is advanced enough (or cell towers plen­ti­ful enough), this inform­a­tion can identify where you live, work, and visit, and even suggest who your doctors are, what congreg­a­tion you belong to, and which nights you didn’t spend at home.  

In its decision today, the Court recog­nized that you have a reas­on­able expect­a­tion of privacy when it comes to your cell­phone loca­tion data. In other words, just by using a cell phone, you’re not declar­ing that you’re comfort­able with the inform­a­tion it collects being public. The Court also reaf­firmed that collect­ing and review­ing your phys­ical move­ments over a period of time consti­tutes a search, which means that without a warrant, the govern­ment can’t access such inform­a­tion.

Carpenter has broader implic­a­tions too. It helps protect the privacy of your loca­tion and asso­ci­ations in sens­it­ive contexts, like polit­ical protests. Prior to this, for instance, police could have obtained extens­ive loca­tion inform­a­tion about the so-called “J20 protest­ors” — activ­ists, journ­al­ists, and other indi­vidu­als arres­ted after getting swept up by police on Pres­id­ent Trump’s inaug­ur­a­tion day — without a warrant. Now law enforce­ment would need a prob­able cause warrant to access cell­phone loca­tion inform­a­tion for such purposes, a crucial safe­guard for our First Amend­ment free speech rights.

2. How are my cell­phone company’s prac­tices and policies affected?

Phone compan­ies collect and store your cell phone’s loca­tion data almost auto­mat­ic­ally. As most people keep their phone with them, compan­ies are able to retain a cata­log of their custom­er’s move­ments, cover­ing a period of up to seven years. This means every cell­phone user could be subject to retro­spect­ive surveil­lance when the govern­ment decides to take an interest in them. This ruling means that, absent emer­gency circum­stances, compan­ies can’t provide your loca­tion inform­a­tion to law enforce­ment unless compelled to by warrant.

3. How might this decision affect my other smart devices and digital records?

Today’s decision could have favor­able implic­a­tions for the level of protec­tion that smart devices and digital records receive. The Court recog­nized that because having a cell phone is a near-require­ment for parti­cip­a­tion in modern life, the fact that cell phone compan­ies collect loca­tion inform­a­tion does not mean you’ve relin­quished your expect­a­tion of privacy. Look­ing to the future, there may be room to extend the Court’s analysis to protect the digital records we create when we use apps for health purposes or smart devices in our homes. Digital devices allow signi­fic­ant and sens­it­ive insights into our every­day lives, and similar privacy protec­tions should also be exten­ded to them. Today’s decision marks a step in that direc­tion.

4. Does the ruling in Carpenter mean that the law has finally caught up with tech­no­logy?

Not neces­sar­ily, but it is a crit­ical step in that direc­tion. Today the Court acknow­ledged the “seis­mic shifts in digital tech­no­logy” and has taken steps to update how the law protects one specific type of record, cell­phone loca­tion inform­a­tion. It recog­nized that tech­no­logy is creat­ing new categor­ies that past rulings do not prop­erly address. While the Court did not expand on how its ruling might be applied to other tech­no­logy or records (like real time track­ing data or cameras), it certainly opened the door for contin­ued advocacy about the privacy of sens­it­ive digital records.