> So how do you protect yourself?

"Sorry, sir, I use a password keeper and left the password file at home. I do not have any passwords with me."

That's not a lie, and I would love for them to explain to the judge if they did ever choose to detain you as to how this is not a valid and legal excuse and non-cooperation in any way.

And if you are in doubt about saying something like this, actually use a password keeper, it's a good security practice.

Further, do not bring any electronic device with you.