Prime Minister John Key says he does not need to read a police report into John Banks' mayoral campaign donations, as he continues to stand by his minister.

The police documents, reported on Thursday by the Herald, revealed that internet tycoon Kim Dotcom told police Mr Banks had asked him for two $25,000 donations for Mr Banks' 2010 Auckland mayoral campaign.

Dotcom said Mr Banks asked him to split his donation into two cheques of that amount so he would not have to declare where the money came from.

The police investigation found Mr Banks had filed a false election return but had not done so deliberately, because he did not read it before putting his signature to it. No charges were laid.


Mr Banks lost the 2010 mayoral bid and is now Act's MP for Epsom and Minister for Small Business.

Mr Key this week stood by Mr Banks, saying he had not broken the law.

He reiterated that on TVNZ's Q+A programme this morning.

"I accept his word, I accept the law is very ambiguous, and I accept that the Labour Party is using this as a politically motivated attempt to get to the Government.''

Mr Key said he did not need to read the police documents.

"I haven't read that police report and I'm not going to because I don't need to ... It's not my job to do a forensic analysis. What I can tell you is, the law doesn't work.''

The Government is seeking a law change that would put a $1500 cap on anonymous donations to local government campaigns.

Mr Key said Dotcom's statements had to be seen in the context of the law.


"The fact that someone tells you they may make you a donation, doesn't mean under the old electoral law that you know that they have.''

Mr Banks has previously denied asking for the donations.

Asked if lying was a sackable offence for ministers, Mr Key said: "The test is whether they enjoy my confidence, and if a minister tells me, 'This is my position and this is what I've done', I accept their word in good faith unless it's proven otherwise.