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.