Somehow, I don't think that passwords are much of a delay for Customs, State, or Fed police.
If you think the perps of said crimes are clever, the law enforcers are even better.
My concern arises from the carriage of Commercial-in-confidence material, or even more important, security classified information. It is an offence to divulge classified material to somebody without an appropriate clearance. Are all Customs officers cleared to Secret level? If I (or somebody else) has classified material, and a Customs officer read that information, would that make me guilty of a breach of the Official Secrets Act?