Reveal your key or else.

[Edgar W. Swank]

Mike Ingle had some good thoughts:

    Since the Canadian case, there's been a lot of talk about the
    problem of being coerced to reveal your key.  If the coercers play
    by no rules whatsoever, there isn't much you can do.  If they
    suspect you of having encrypted data, they will beat it out of
    you.  ...

Hypnosis might offer a defense here.  A post-hypnotic suggestion could
make it impossible for you to remember the passphrase in a coercive
situation.  Even better, you would remember -very clearly- an
-incorrect- passphrase unrelated to the correct one.  The more
stressful the situation, the more you could think of -nothing else.-
You could then put on a convincing performance that you are baffled
why the passphrase you are "sure" is the right one doesn't work any
more.

    Steganography can hide your data, but then you have the steg
    program itself.  If they find the program, they have reasonable
    grounds for assuming you have hidden data, ...

Then better hide the steg program.  A good design would be like LZEXE,
that would attach itself to any program, and would just pass through
any command line except a pass phrase. It would require highly skilled
analysis to detect the steg program hidden in, say, your GIF viewer or
WAV player.

This takes nothing away from Mike's suggestion of having different
passphrases access different data.

--
edgar at spectrx.saigon.com (Edgar W. Swank)
SPECTROX SYSTEMS +1.408.252.1005  Cupertino, Ca