Even before Judith Collins' surprise Saturday resignation, there's been no shortage of hot water for National MPs and their allies to get into. Here's a look back at some of those who have fallen since National took power.
JUDITH COLLINS, 2014
A 2011 email sent to John Key's chief of staff last night suggested the Minister of Justice had undermined Adam Feeley, the then director of the Serious Fraud Office. This was the final straw for John Key, who said, "It's not tenable for me as prime minister to be given this email and not to act."
Earlier in the year, in May, Key had put Justice Minister Judith Collins on a final warning after she withheld details of a dinner in China with a company linked to her husband. The dinner was with senior members of Oravida, a company that deals with New Zealand dairy products, and a senior Chinese government official. Collins' husband David Wong-Tung is a director of the company. Key said the cumulative effects of her interactions with Oravida could lead to a perception of a conflict of interest.
GERRY BROWNLEE, 2014
Running late for a plane, Transport Minister Gerry Brownlee admitted he "without thought breached airport and airline security rules by entering the gate lounge through a door usually used for exit only". It no excuse for bypassing a security check. His offer to resign was due to him having broken aviation rules and put those responsible for security in a compromised position.
CHESTER BORROWS, 2014
Busted for speeding near Patea, in Taranaki. The Courts Minister and a former police officer, he was pulled over at Whenuakura while driving 11kmh over the limit. He was running late. It was a fair cop, he said. "I was quite rightly ticketed, which I have paid."
CLAUDETTE HAUITI, 2014
Removed herself from contention for the coming election, after a call from Prime Minister John Key. She had come to be seen as a liability for the party after it emerged used her Parliamentary purchasing card to pay for a Christmas trip to Australia. That trip, and other unauthorised spending led to the list MP returning the card to Parliamentary Service in March.
MAURICE WILLIAMSON, 2014
Maurice Williamson erred in contacting police about an investigation into a wealthy Chinese businessman he had links to, after Donghua Liu was arrested for a domestic assault. Key accepted Williamson's resignation after he was made aware of the issue. "It's a very long establishment that MPs don't interfere with police, " Key said. "There's no grey in this, in the end there's a line. The moment he made the phone call he crossed the line."
PETER DUNNE (UNITEDFUTURE), 2013
Accused by NZ First leader Winston Peters of leaking the Kitteridge report to Fairfax reporter Andrea Vance he was unable to prove to he was not the source of the leak to an investigation, so resigned as a minister. He was reinstated in January 2014.
JOHN BANKS (ACT), 2013
May well be remembered as the first political victim of Kim Dotcom. The ACT leader and the party's sole MP resigned his small business and regulatory reform portfolios after a judge ordered him to stand trial over allegedly filing a false electoral return. The private prosecution was brought over $65,000 in donations to his 2010 mayoralty fund from internet mogul Dotcom and casino company SkyCity. The donations were registered as anonymous. Dotcom revealed the cash gift. Resigned from Parliament in June, after he was found guilty in the High Court.
AARON GILMORE, 2013
Behaved "rudely" to bar staff at a Hanmer Springs hotel, then was accused of misleading the Prime Minister's office over threats to have a waiter sacked, and of lying to reporters about his departure from the Ministry of Business, Innovation and Employment. Gilmore blamed the "intense pressure" of scrutiny, which was a distraction to the Government and meant he could not function as an MP.
NICK SMITH, 2012
Smith handed in his resignation from all his Cabinet portfolios, including as ACC minister, after coming under pressure for writing a reference letter on ACC letterhead for National Party activist and ACC claimant Bronwyn Pullar, who was seeking help with her case. Key welcomed Smith back into Cabinet after a reshuffle.
PANSY WONG, 2010
Key said he would have sacked the ethnic affairs minister if she hadn't resigned. Wong used her travel entitlement to pay for parts of her husband's trip to China in late 2008, where he conducted private business - MPs are forbidden to use the entitlement for business purposes.
PHILIP HEATLEY, 2010
Heatley resigned from housing and fisheries portfolios after misspending taxpayers' money. Reinstated a month later after an auditor-general's inquiry found that while he spent $1402 wrongly, he did not intentionally break the rules.
RICHARD WORTH, 2009
Worth resigned as internal affairs minister and from other portfolios after it was alleged he offered a woman a job in return for romantic favours. Police investigated after the woman laid a complaint, but no charges were laid.
Should the speed limit be raised to 110kmh on some roads?Related story: 110kmh limit moves closer