Should I change the title? I don't see how it violates any rules? It's not click-baiting either. Unfortunately it's quite a summary of what the article says ...
UK was asserting that Miranda was involved in espionage and terrorism, but you're asserting that it was journalism (carrying documents on behalf of Greenwald) and I don't think that's really accurate.
Well he was carrying documents meant for a journalist, that where to be published by a legit newspapers. Sounds like being a part in a journalistic process to me.
Sure the title maybe a bit edgy, but that it what it comes down to. That is the important (and very bad) message.
For some values of "they", not including (yet) the court where this document was read out, right?
Because at the moment that value of "they" includes (from the article) Scotland Yard, and (from outside the article) a few other similar organisations (maybe GCHQ, MI5, MI6, etc)
But certainly not "the UK". So the title, as well as being editorialized, is an exaggeration.
EDIT: But let's see what happens with the court case, I guess.
'In an email to Reuters, Greenwald condemned the British government for labeling his partner's actions "terrorism."
"For all the lecturing it doles out to the world about press freedoms, the UK offers virtually none...They are absolutely and explicitly equating terrorism with journalism," he said.'