I suspect the legality of the hardware is going to be less of an issue than the very grey area regarding probable cause for search and seizure. LEOs will be walking a fine line here. Criminal charges won't stick without a legal search based on probable cause. I see this ultimately being tested in higher courts.

Even if charges don't go anywhere, a more proactive stance on the part of police may serve as control rods in the reactor -- trying to prevent meltdowns instead of cleaning up afterward. Whether or not this will work is frankly up in the air.