We might think of most of our day-to-day activities as private. Rarely is anyone deliberately eavesdropping on our conversations, spying on where we shop or following us on our commute. The government needs a search warrant or other court order to listen to our phone calls, to discover what books we checked out from the library or to read our mail.
But a tsunami of digital tracking technology has made a large portion of our lives public by default. Nearly everything we do online and on our phones — our movements, our conversations, our reading, watching and shopping habits — is being watched by commercial entities whose data can often be used by governments.
One of the last bastions of privacy is encrypted messaging programs such as Signal and WhatsApp. These apps, which employ a technology called end-to-end encryption, are designed so that even the app makers themselves cannot view their users’ messages. Texting on one of these apps — particularly if you use the “disappearing messages” feature — can be almost as private and ephemeral as most real-life conversations used to be.
However, governments are increasingly demanding that tech companies surveil encrypted messages in a new and dangerous way. For years, nations sought a master key to unlock encrypted content with a search warrant but largely gave up because they couldn’t prove they could keep such a key safe from bad actors. Now they are seeking to force companies to monitor all their content, whether or not it is encrypted.