[istjohn]

Here's a quick and dirty DIY system:

1. Create 10 files of encrypted random data. Discard the passwords.

2. Replace a random selection of these files with encrypted fake data, using different passwords for each one.

3. Replace one file with the actual encrypted data.

If challenged, openly share this scheme you used with your opponent. Under durress give up the passwords to the fake data files. Insist that one fake data file is the real data and that the keys to all the other files were discarded.

[tsujp]

Get punished anyway because "only bad people have things to hide" would be my guess. It's a shame we even need to have plausible deniability in the first place.