What a revolting week in National Party politics.

Surely when Simon Bridges sat down at the beginning of it to finger Jami-Lee Ross as the leaker of his expenses he could never have imagined the hand grenade he was about to detonate.

Of course, he could have avoided the mire that National now finds itself in right from the start by not publicly launching an inquiry and instead of handling it in-house. He obviously thought that the leak wasn't from within, wrongly suspecting it was closer to the Speaker's office.

How wrong he was and how mortally wounded he now is from the shrapnel.

National's bleeding heavily, not helped in any way by its flame-throwing decision to destroy its feral MP Jami-Lee Ross. He'd done that all by himself without any help from the party he still proclaims to love.

Ross eluded to what he said were totally unfounded sexual harassment claims at the beginning of the week, with pure as the driven dross Paula Bennett jumping on the bandwagon saying he was guilty of behaviour unbecoming of a "married MP" and the scandal deepened. Now the bedroom door has been opened and the sheets have been lifted with four anonymous women talking about how they were bullied and manipulated by the political predator.

Bennett was quick into the fray, calling the women incredibly brave for speaking out. National's doubling down on an area of politics that has largely been off limits until now, but anything goes it would seem in this unseemly stoush.

Taking the moral high ground Bridges declared Ross would have been chucked out of the party much sooner if he'd known about the claims of alleged sexual relationships and harassment that have now come to light. But then he was at a meeting at the beginning of the month with Bennett where the harassment allegations were discussed before they sent the MP on indefinite leave.

Forget the inconsistencies in their stories, it's a bit rich for them to say now they only found out a few weeks ago about the allegations that have been swirling around this place for many weeks. If they're to be believed they must have been the last to know and of course, they weren't.

Neither the National leadership nor Ross has ended the week well, it's been a tawdry, damaging affair that could have been easily avoided.

Ross is over and out, he's been the underhand author of his own demise. Bridges is likely to survive in the short term essentially because no-one wants his job at the moment, but wait until the party's polling takes a hit as it almost certainly will.

The one person who's been smiling through all of this is the wily old fox, Winston Peters.