When the news broke that a commercially- and budget-sensitive Cabinet paper had been leaked to Telecom, I think everybody was expecting political or corporate skulduggery was to blame. It turns out to be nothing of the sort. Rather than warring Ministers or Telecom having a mole within the public service, it was just an ordinary public servant being a dick. And while precautions can be taken, there's ultimately not a lot that can be done about such a situation, except to fire the individual responsible after the fact.
Despite this, Gerry Brownlee is still trying to make out that it is somehow All The Prime Minister's Fault. But its very difficult to see how. She's not responsible for staffing decisions, not responsible for police background checks (which in any case turned up nothing unusual), not responsible for the psychological profiling of staff (ditto), and ultimately, not responsible for their personal moments of misguided stupidity. The leak was not the result of incompetence or systemic failure in her department; rather, it was the fault of one man betraying the immense trust placed in him in a misguided attempt to help out a mate. In such a situation, what matters is how the Prime Minister responds - and I don't see anything there which might call her competence into question.