The British have a way round this:
Alice, in the UK, makes sure all her passwords are too long to remember. So she stores them with Trent, in the USA.
Trent has been told only to reveal Alice's passwords if she has phoned him with her daily dead man's handle.
Plod, also in the UK, asks Alice for her passwords citing RIPA 2000. Alice is held at Plod's luxurious police station for a day, then tells Plod that she hasn't stored them in the UK because they're too long to remember and that Trent has them. Plod calls Trent, who not having received yesterday's dead man's handle, pleads the 5th.