[citation][nom]waxdart[/nom]In the UK he would have been banged up for not handing over the keys![/citation]
If you're savvy enough to encrypt your harddrive, then I suspect a criminal in the UK would simply use Truecrypt's hidden encrypted volume feature. That way, he could give the police one key, after putting on a good show of refusing to comply, and they would still have nothing to charge him with.
In the U.S., they are still debating the legality of trying to force someone to give up an encryption passphrase. The 5th Amendment of our Constitution provides, among other things, protection against self-incrimination. Defense attorneys have taken the position that the contents of someones own mind, to include encryption passphrases, are thus protected. While I hate to see criminals get away with things. From a privacy standpoint, I believe this is a correct interpretation of the law.