You also are missing the point of TrueCrypt: Plausible Dependability and multiple passwords for different content. It'd be like "Give us the key to this safe that unlocks the incriminating evidence, even though we have absolutely no way of knowing if you're hiding more or giving us the full truth".
You could have cat pictures encrypted with passphrase A and incriminating evidence (that stands up to the best forensic analysis currently available) encrypted with passphrase B and they wouldn't know which is which, if they unlocked ALL the data, or what.
Truecrypt is AMAZING and anyone holding onto stuff that might get them into trouble (esp. w/ foreign gov'ts) should use it.
Where did you put your ex-wife's body Mr Johnson, we know you killed her? Just point at the map, you do not even have to say anything.