Does biometric access to phones require a warrant?

Byline: Nicole Black

A decade ago, smartphones were in their infancy. The iPhone was new and widespread adoption had not yet occurred. Many were suspicious of the touch screen interface, and lawyers in particular clung to the idea that they required the tactile feel of a traditional keyboard.

Fast forward to 2019, and smartphones are commonplace even among lawyers. In fact, according to the latest ABA Legal Technology Survey Report, 95 percent of all lawyers use smartphones on a daily basis.

Not only has smartphone usage grown over the past decade, so too have the technologies that power the devices. Today's smartphones are essentially minicomputers with memory and processing power comparable to that of some desktop and laptop computers. For that reason, smartphones have become indispensable and people store all sorts of information on them.

It's no surprise then that law enforcement routinely seeks access to smartphones of suspected criminals. Of course, constitutional protections still apply. For example, for a number of years now, it has been generally accepted that law enforcement cannot require you to provide the password to your smartphone, since doing so is compelled testimony and thus falls under the protection of the Fifth Amendment.

However, with the release of smartphones with biometric unlocking features, the waters were muddied. Many courts subsequently concluded that the biometric data used to unlock phones (i.e., fingerprints and faces) is not inherently testimonial and thus requiring a defendant to open a device using biometric data does not violate the Fifth Amendment.

The tide may be turning, however, with the release of a recent federal district court decision on Jan. 10. Northern District of California Magistrate Judge Kandis A. Westmore considered this very issue and issued an important ruling in The Matter of the Search of a Residence in Oakland, California. Specifically, the court considered whether law enforcement should be granted a search warrant that required any individual present at the time of the search could be compelled to "press a finger (including a thumb) or utilize other biometric features, such as facial or iris recognition, for the purpose of unlocking the digital devices found in order to permit a search of the contents"

In refacing its decision, the court first concluded that the search request was overly broad, and that there was insufficient probable cause to: 1) compel anyone other than the...