I think we all agree we want our politicians and public servants to be like Caesar's wife - above suspicion.

Former Green Party co-leader Metiria Turei's goose was cooked when she blithely told the nation she ripped off the benefit system when on the DPB. No justification could save her political skin, although the fact she was totally unrepentant didn't help.

Prime Minister Bill English, too, came in for a fair amount of political heat when found claiming a generous accommodation allowance. Legally, he was entitled to it, morally he was not and had he not paid it back and had it been an election year, he might not have got away with a public bollocking.

We don't like cronyism either. When it was found former Prime Minister John Key had encouraged his mate Ian Fletcher to apply to be head of the country's spy agency, there was finger pointing and demands for explanations.


Key's notoriously unreliable memory failed him again - "I haven't seen the guy in a long time" became "I've twice had breakfast with him [in the past couple of years] in a very short space of time".

Still, Key's unique non-stick surface, which could be sold for a fortune to politicians around the world, protected him and he lived to smile another day.

Perhaps, in part, it's public vigilance and righteous indignation that helps keep New Zealand up there when it comes to our lack of corruption. We have topped the Corruptions Perception Index as the least corrupt country for seven straight years, generally sharing the top spot with the squeaky clean Danes.

There was a fall to fourth place in 2015, mostly due to political interference in Official Information Act requests - think Serco and the Auckland City Convention deal. We regained top place last year, but given continued faffing and procrastination of ministers and their staff over OIA requests, we may slide once again - think the allegation the Transport Minister's office meddled in an OIA request for a KiwiRail report.

We can't afford to become complacent. And it's important to hold our political overlords to account. But what about us? Do we have the same expectation of ourselves to behave scrupulously?

Supporters of Turei said anyone who ever paid cash for a job around the house was just as culpable as Turei. No one can stand in judgment of her, because we are all guilty of defrauding the system.

Whether you accept that kind of moral relativism, what became apparent was the black economy is alive and well here.

People justified cashies as being a way for the honest working man to get what he is owed. Multinational companies avoid paying billions in taxes, beneficiaries rip off the system and sleazy white-collar sharks employ equally sleazy lawyers and accountants to minimise their taxes. Cashies are the Ordinary Joe's way of getting a fair share.

Every country has its black - or shadow - economy. In the UK, the shadow economy makes up 11.5 per cent of GDP. That's roughly the same as this country - here it's about $9 billion or 12.5 per cent of GDP.

It's difficult to stamp out because of the number of people and the low amounts changing hands. It's also difficult because people don't see it as stealing - they see cash-in-hand jobs as something they're entitled to.

When there was a Dob in a Beneficiary campaign in the late 90s, more than 11,000 calls were made to the anonymous tip off line. Dob in a Tradie for Cashies saw just hundreds of calls made to the IRD.

We should be proud of our lack of corruption. And it's good to hold those receiving public money to account - be they public servants or beneficiaries.

But integrity and accountability goes both ways. If we apply them to others, surely we should apply them to ourselves.