As leaks go this one shouldn't even have caused a ripple on the surface.

The details of Simon Bridges use of a ministerial limo, which he's entitled to, for a getting-to-know your tour around the country, leaked almost two months ago, has become something of a political tidal wave.

Boiled down, the taxpayer wasn't any worse off for the eighty-odd thousand bucks he racked up for using the limos which we already own.

It was a book entry from one department to another. And the details were due to be released anyway, the leak was simply getting the spending out early.

It wasn't anywhere nearly as serious for example as the leak of the pension overpayment to Winston Peters during the election campaign and wasn't within cooee of the leak that there was about to be a leadership change in the National Party earlier this year.

The issue now has nothing to do with his use of limos, that's become lost in the mire.

It's the way the leak was handled by the politicians that has turned it into something it should never have been.

The cops within days knew who sent a text that sparked the leak but they weren't telling anyone saying the person had mental health issues.

The politics of it began with Speaker Trevor Mallard, who's responsible for the bureaucratic arm of the Government that held the spending details, ordering an inquiry into who leaked the material, which seemed fair enough.

Then before it could get under way he inexplicably called it off indicating the leak came from the Nats.

There was no proof of that and at that point National's leader Simon Bridges should have backed off and let matter lie.

If he had, by now the matter would have been long forgotten, along with all the ministerial expenses that have long since been released and are now fish and chip paper.

But Bridges added fuel to the fire by ordering his own inquiry which has now dragged on for weeks and which saw one of his stressed MPs Jami-Lee Ross standing down from Parliament for an indefinite period for personal health issues.

Scuttlebutt within the party had long been fingering Ross as the leaker but he's given Bridges assurances that he wasn't.

Just to remove suspicion from himself and his staff we now find out The Speaker privately called in the IT experts and an employment lawyer to ferret out any possible transgressor and the finding of that has just mysteriously made its way into the media, exonerating his office which points the finger back at National but implicates Mallard in a way that he shouldn't be as a " politically impartial" officer of Parliament.

So this leak has become a sieve and once National drains it, next week I'm told, leaving a solitary figure sitting exposed to leader Bridges, he has to act.

Anything short of that would undermine his leadership even more than it has been already during this shambolic schmozzle.