How would one claim plausible deniability?
"Your honor, I was simply transmitting random ASCII to a friend! He replied with random PETSCII!"
Well, that sort of argument by itself will just get you into deep trouble. (Taking the piss with a court is a good way to get into trouble, and your argument is hardly plausible in the first place.) Steganography might work, but then you've got the problem of distributing the baselines so that the other party can decrypt; sending lots of visually-identical-but-not-bit-identical copies of the same image would usually be a dead giveaway that you're using steganography.
Or that you use Google+; I keep seeing the same old shit resent there.
It's far better to ask why the AG Hates Australian Business, given that he's trying to make all online commerce impossible. Or that he hates medical privacy because he's making it impossible to securely transfer patient records between doctors and hospitals. Find things that show why encryption is an important basic part of doing things online that is used for nefariousness only because it is used for masses of other things too. ("Cars are used to commit smash-and-grab raids! Ban them at once!")