In the United States, anyone can invoke the 5th amendment and refuse to give tesimony that incriminates themselves.
Another way to think of this is that our Constitution privileges information that is contained in personal, physical memory. It is subject to protections that memories stored in, say, a notebook, or physical photographs, are not.
The debate over encryption hinges on thinking of a computer or a phone as “property”, but a 2014 Supreme Court ruling (more details) acknowledges that the intimacy of the knowledge that is contained on cell phones makes them subject to special consideration:
Chief Justice John G. Roberts Jr., writing for the court, was keenly alert to the central role that cellphones play in contemporary life. They are, he said, “such a pervasive and insistent part of daily life that the proverbial visitor from Mars might conclude they were an important feature of human anatomy.”
“An important feature of human anatomy” is a key sentence there. As the interface for the computer moves closer and closer to the physical body, and people argue that always-on access to the internet actually functions as an extension of our brains, maybe it’s time to start thinking of computers as a prosthetic, privileged in the same way information in my mind is, and not as property.
We can think of this in reverse — let’s say that neuroscience discovers a way to “decrypt” memories in the brain. Can the government compel you to undergo that procedure with a subpoena? Would the 5th amendment apply in that case? Because I’m not “giving testimony”, but the memory that the 5th Amendment generally bars access to is available without my testimony. So do those memories just become property, subject to a warrant?
This is what’s actually at stake with respect to encryption of digital devices. The court has already recognized that intimacy of information creates a special category of consideration. So if it’s not established that when I’m using something as an auxilary memory, it deserves the same protection as my regular memory, the contents of my regular memory also eventually become fair game.
This isn’t a well-developed thought but it’s worth thinking about. We already use computers as prosthetics, and we should start acting like it.