At this point setting up a secure connection to a device in a secure location is way easier than trying to protect your data against someone with physical access.
You can also get your collaborators to revoke access if you fear you might be 'compromised', although ultimately it's hard to protect a system against yourself.
I believe Truecrypt supported a feature where different passwords would unlock different partitions in a volume. So someone could ask you to input the password for BadBoy.tc, and if you enter password1, then you get say the data they actually want. But if you enter password2, it mounts a different part of the file which gives the appearance that you unlocked the whole thing. So, you could stage a dummy partition that has false but convincing data and hopefully fool any captors.
2) that’s still true even if the reason you don’t have a key is because you don’t actually have a secret encrypted partition — or whatever — to supply a decryption key for
So the best thing to do is avoid being in a situation where someone is allowed to do that in the first place.
This is interesting. This also means that using encryption or anything that can plausibly make someone even slightly suspect you're using encryption (even if you are not) can make your situation worse, with certain classes of enemies.
I'm sure advanced configurations with well-crafted decoys and steganography can help combat that, but as we can see, encryption can only take you so far and it's only one element of the picture.
Plausible deniability, like hidden containers in TrueCrypt?
That's a double edged sword though - imagine you give up, surrender the password and are then being asked to unlock a hidden volume, which you don't have.
Encrypt with two keys, one that you know and one that a trusted third party , knows. When you reach your destination, establish secure contact with the third party and have them share their key.
I think one method would be to ensure you don't have the full key, i.e. you have some select friends, each that have part of the key (with some redundancy) - all unaware of one another and potentially all unaware that they even have part of the key.
Then you position your friends over multiple jurisdictions so that they cannot legally compel all of them to play along.
Sharded secrets... you only have one part of a key or keys needed to decrypt some data so even extracting that from you by torture will not suffice. Of course this isn't always practical.
The trick is to ensure you are never near all the people who know the secret when there is the possibility of trouble. That makes kidnapping everyone harder.
Of course if you really worry about such things you shouldn't be trusting the other people you are working with either...
At this point setting up a secure connection to a device in a secure location is way easier than trying to protect your data against someone with physical access.
You can also get your collaborators to revoke access if you fear you might be 'compromised', although ultimately it's hard to protect a system against yourself.