Paul Chambers' conviction for sending a message "of a menacing character" has been overturned on appeal.
Rightly so – because it was always obvious (to everyone except, amazingly, the original judge in the case, and the judge at the first appeal) that his tweet: "Crap! Robin Hood airport is closed. You've got a week and a bit to get your shit together otherwise I'm blowing the airport sky high!!" – was a joke.
It's a kind of irony and/or parody: his message was something like: It's crazy to say "You've got a week and a bit to get your shit together otherwise I'm blowing the airport sky high!!"
Various comedians were called as experts in the case, but I'm not aware that they asked any linguists to comment, which is a bit of a shame. On the other hand, here pragmatics ≈ common sense, in that the intuition is clear enough to everyone. (Except the first two judges, as I said, and they get slapped down with some force in the new judgement: "We have concluded that, on an objective assessment, the decision of the crown court that this 'tweet' constituted or included a message of a menacing character was not open to it.)
Guardian story here.