John Key is right not to release his tax returns. There's no doubt it would be news and would feed the nosy-parker in us but it would not serve the public good.
We need to encourage our best and brightest to stand for office but it's getting harder and harder as the public realm encroaches ever further on the private.
I have spent a great deal of time getting good people to stand for Parliament - and not just for my own party. It's hard. And one of the biggest turn-offs is the level of scrutiny applied to private lives. It's hard to advise potential candidates because there's no guarantee of what's in and what's out.
It changes with the times and what's in the news. The British Prime Minister has tabled his tax return so the question is asked of ours. To the best of my knowledge no Prime Minister has previously been asked.
In 2007 it was visits to strip clubs. Then Australian Opposition leader Kevin Rudd was in the news admitting to a drink at a "gentlemen's club" with a news editor and another MP in New York four years earlier.