I'm British actually, my Kiwi friend.
Firstly, I'm curious as to what the Official Secrets Act has to do with this. These leaks were not pertaining to state secrets, issues of national security or anything like that. They were politically embarrassing. Heck, if the OSA applies to information about the Houses of Parliament having a illegal immigrant as a cleaner, that's rather insane (and a huge leap for the OSA)
Now, if you want to say the civil servant was in breach of the OSA, you might have a leg to stand on. However, other breachs of the OSA haven't resulted in prosecutions under the OSA of those people who recieved documents, only those who gave them out. Further, whats with the police saying Green 'groomed' the civil servant. Can they pick some less inflammatory language?
Secondly, MP's should not be above the law, no. I never said that, as you'd know if you read my replies. What should be protected is Parliamentary Privilege, in just the same way as lawyers and doctors privilege is. How can an MP do his job if his parliamentary offices are raided? That's the biggest offence here, and thats why the Speaker should resign for allowing it.
Thirdly, stop parroting the labour line. Its kinda hypocritical too, given that the current government has interferred directly with police investigations before. (Saudi Fraud Investigation)
Forth, you say its corrupt to institute leaks? Interesting. Everyone leaks! Gordon Brown made his name through leaks! A famous quote goes 'The Ship of State leaks from the top'.
Finally, the idea that ministers didn't know about this is ridiculous. The police informed Cameron, Johnson and the Speaker. First, do the police inform your boss if they go arrest you? Or the mayor? So its clear the police knew there were some political problems with this, along with some constitutional problems, as they informed the Speaker (who failed in his job). Most poltical commentators have said that the idea they did this and didn't think that political cover wasn't needed is just stupid. The ex head of the flying squad said he'd inform ministers before hand (but obviously not ask for permission)