I believe the technician who found incriminating and illegal material on Gary Glitter's computer was legally obliged to inform the police. He didn't 'steal' the material, he brought it to their attention.
The guy who copied EV's financial files committed a breach of confidence, however you look at it, but wasn't prosecuted for it.
John was provided the material, and leaked 1 or 2 of the 11 files, out of what he genuinely believes to be public interest.
What pisses me off about the affair is the way M and EV have handled it. By invoking an Anton Pillar warrant (or whatever the correct term is), they have apparently taken a forge hammer to crack a hazel nut. That is, if the remaining files are as innocuous as the posted 2 seemed to me (I didn't see any conclusive evidence of any wrong-doing). Of course, the remaining ones may tell a different story.
I can't believe how inept EV and their lawyers' strategy has been from the public relations angle. In addition to the draconian methods they employed on John (surveillance, 4 month gagging order and so on), horse's-head-in-the-bed Scattini was dumb enough to refer on radio to John bolting like a scalded cat, and subversive groups in dimly lit rooms, or whatever.
All this is dumb enough to make you cringe. It's worse than a crime, it's just a fucking dumb mistake on their part.
And the really awesomely vindictive part is not just writing to John's employers when he didn't have a chance to defend himself, but, even more despicably, contacting the Arts Council from whom he has received a grant to write a book, to try to destroy his future chances there.
What a bunch of totally inexpressible bastards.