I've nothing to hide - Banks

John Banks says he's got nothing to hide.

The ACT leader is reacting to a complaint by Labour MP Trevor Mallard to Auckland's Electoral Officer over a $15,000 donation to the Epsom MP when he was campaigning to be Auckland's Super City mayor in 2010.

It came from SkyCity and Mr Mallard alleges Mr Banks has broken electoral law.

But Mr Banks vehemently denies that.

"There were many donations that I received anonymously that were given to the campaign, lodged to the campaign, that I wasn't aware of and the Act clearly defines that as being according to the Act."

Mr Banks says he only found out the $15,000 was from SkyCity a few months ago.

The police will investigate the $15,000 donation.

Labour MP Trevor Mallard made the complaint and says Mr Banks wrongly filled out his declaration of expenses.

"If it was given to his campaign by a known person then it should be declared, it can't be declared as anonymous, can't keep a candidate in the dark and pretend that they don't know where the money's coming from."

Photo: John Banks (Getty Images)