> Do we really, really, fully understand the implication of allowing private contracts that trump criminal law?
...it's not that at all. We don't want private contracts to enshrine the same imbalances of power; we want those imbalances rendered irrelevant.
We hope against hope that people who have strength, money, reputation, legal teams, etc., will be as steadfast in asserting basic rights as people who have none of those things.
We don't regard the FBI as a legitimate institution of the rule of law, but a criminal enterprise and decades-long experiment in concentration of power. The constitution does not suppose an FBI, but it does suppose that 'no warrant shall issue but upon probable cause... particularly describing the place to be searched, and the persons or things to be seized' (emphasis mine). Obviously a search of the complete digital footprint and history of a person is not 'particular' in any plain meaning of that word.
...and we just don't regard the state as having an important function in the internet age. So all of its whining and tantrums and pepper spray and prison cells are just childish clinging to a power structure that is no longer desirable.
I think legally the issue was adjudicated by analogy to a closed safe: while the exact contents of the safe is unknown beforehand, it is reasonable it will contain evidence, documents, money, weapons etc. that are relevant, so if a warrant can be issued in that case compelling a locksmith to open it, then by analogy it can be issued against an encrypted device.
Without doubt, this analogy surely breaks down as society changes to become more digital - what about a Google Glass type of device that records my entire life, or the glasses of all people detected around me? what about the device where I uploaded my conscience, can law enforcement simply probe around my mind and find direct evidence of my guilt? Any written constitution is just a snapshot of a social contract at a particular historical time and technological development point, so it cannot serve as the ultimate source of truth regarding individual rights - the contract is renegotiated constantly through political means.
My question was more general: how could we draft that new social contract to the current age, how could we maintain the balance where the encrypted device of a suspected child predator and murderer is left encrypted, despite the fact that some 3rd party has the key, because we agreed that is the correct way to balance freedoms and law enforcement? It just doesn't sound stable in a democracy, where the rules of that social contract can change, it would contradict the moral intuitions of the vast majority.