Outrageous and (obviously) unconfirmed claims. But again, and as an American whose private data should never fall under the purview of FISA or FAA or any other IC intelligence gathering activities, I don't seriously doubt domestic US spying/surveillance capabilities.

That LE has to feign the need for a warrant should the need arise to make lawfully admissible that which they already know and are in possession of is the most likely scenario. Encryption really is the only safeguard.