You have to first prove whether the device even has an encrypted container in the first place.
No. That is pure naivete.
The government will claim that you do have an encrypted container and hold you until you divulge the alleged key to the alleged data they claim you have, until the data looks like what they are looking for. That is the current reality.
I've been saying for years that people should encrypt everything, ESPECIALLY the mundane and boring stuff that you don't even care about hiding. If you read old cyberpunk SciFi (True Names etc.) it was assumed that in cyberspace, everything would be encrypted and everyone would be pseudonymous, because these pre-Internet pioneers could see the ramifications of doing otherwise.
We will probably get there eventually. Kim Dotcom (of Megaupload fame) got his mansion raided, cars and other toys stolen, and assets frozen for alleged criminal charges (mere copyright infringement wasn't enough to extradite him to the US; so the Hollywood shills at the FBI brought criminal money laundering charges instead). Now he's working on a new Megaupload concept where all content is encrypted by the user so that Megaupload itself doesn't know what the data IS, and so it can have perfect plausible deniability as to its legality, and also, the government can't find incriminating data even if it does raid their servers, because it would all be encrypted. Proper hackers have been saying 'well duh, that's the way you should have been doing it from the beginning' for decades now.
I have a feeling the next generation may have a much better understanding of public-key encryption and two-factor identification. And I'm not sure if I should be sad about that or relieved.