The whole point is that in technology, there is no such thing as privacy/secrecy that's conditional on having a legally proper warrant.
Either the data or system is secure, or it isn't. Technologically, if there is a way for a judge to authorize reading a single X; then it is a hole that eventually will allow to read all X without the warrant by others as well.
As an example, if a cellphone network software allows for FBI wiretaps, then that can be used also by illegal wiretapping (http://en.wikipedia.org/wiki/Greek_wiretapping_case_2004%E2%... - the criminals weren't even identified). And if a system is secure (for any reasonable definition of the word secure), then noone can break that security, no matter what warrants they have.
There is no middle way. If I'm allowed to protect my communications from random illegal snoopers (say, corporate espionage); then that protection will be just as effective against legal snoopers.
If digital locks are treated as physical locks, a warrant would compel you to decrypt your files. If you refuse, that is obstruction of justice. Also, correct me if I'm wrong but I think there are few forms of commercially available encryption the government could not crack given time + resources, which a warrant would provide.
1) When properly used, commonly freely available encryption should be unbreakable even when given completely unreasonable resources (i.e., a Manhattan Project scale effort). Alternative methods (e.g. kidnapping&torture of everyone who might have access to keys and their relatives) would be far simpler and cheaper than actually bruteforcing proper cryptography.
2) There are freely available steganography/hidden volume tools that make it impossible to verify IF there is something encrypted - for example, you might guess that a hidden volume exists, the accused may decrypt N hidden volumes, but noone would be able to check if there is another N+1'st volume for which a key was not provided.
Either the data or system is secure, or it isn't. Technologically, if there is a way for a judge to authorize reading a single X; then it is a hole that eventually will allow to read all X without the warrant by others as well.
As an example, if a cellphone network software allows for FBI wiretaps, then that can be used also by illegal wiretapping (http://en.wikipedia.org/wiki/Greek_wiretapping_case_2004%E2%... - the criminals weren't even identified). And if a system is secure (for any reasonable definition of the word secure), then noone can break that security, no matter what warrants they have.
There is no middle way. If I'm allowed to protect my communications from random illegal snoopers (say, corporate espionage); then that protection will be just as effective against legal snoopers.