Earlier quoted context omitted.
A few points - Devils advocate, travel back to the 1950s. The government searches your home and takes a letter or other document that is clearly written in code. Can/would they jail you as in the current case until you decode it? And without even charging you with any other crime first? At what point is "I used a one time pad" or "I don'remember" sufficient? I'm sure all of us have at least once (probably many) times…
Following from this, if perfect encryption leaves a ciphertext indistinguishable from random noise, then what proof does the court expect that a given decryption is the correct decryption? If he were to hand them an elaborately constructed fake file system, who would they be to say those weren't the encrypted contents? (For purposes of thought exercise, mooting arguments about headers / magic fingerprints / leaky met…
How would the authorities know you have given them the correct password?
I'm not sure how effective it was, I remember there being some criticism of it.