Kim Dotcom vowed to "destroy" John Banks and Prime Minister John Key, MP Mark Mitchell has told the High Court in Auckland.
Mitchell, the National MP for Rodney, today gave evidence for the defence at ACT MP Banks' trial for filing a false electoral return.
Mitchell said he had met Dotcom at a barbecue in his electorate where the internet entrepreneur was "agitated" about the case to extradite Dotcom to the US on criminal copyright charges.
He said Dotcom told him: "I'm going to destroy John Key, I'm going to take down John Banks, I'm going to take down the Government."
Mitchell's other evidence was suppressed.
Banks, the Epsom MP and former leader of the ACT Party, is on trial for "transmitting a return of electoral expenses knowing that it is false in a material particular".
The charge relates to three entries in the electoral returns for his failed 2010 Auckland super-city mayoral campaign.
The donations were recorded as anonymous, but the Crown says Banks knew two donations of $25,000 were from Dotcom and one of $15,000 was from SkyCity.
Earlier today, Justice Edwin Wylie summoned senior TV3 management to court and banned them from filming the rest of the trial.
The channel last week broadcast a controversial clip of Banks appearing to pull something from his ear, look at it and eat it while sitting in court.
Justice Wylie said the footage appeared, on the face of it, to be intended to expose Banks to "ridicule and derision".
TV3 lawyer Clare Bradley said there was "no getting round that it was a bad judgement call".
She and news and current affairs deputy editor Richard Sutherland had decided to run the clip to demonstrate Banks' reaction to audio of his police interview, she said.
They had considered that there were no fair-trial implications and that Banks was a public person who would be able to withstand the attention, Bradley said.
Bradley said the clip was now on YouTube but no-one from TV3 had put it on the site.
Bradley said an apology to Banks would be broadcast tonight.
The judge banned TV3 from using any recordings it had already made and said it could not film any future sittings of Banks' trial.
AMANDA BANKS: NO TALK OF MONEY
Banks' wife, Amanda, testified this morning that when she and her husband visited the Dotcom mansion the upcoming mayoral elections had not been discussed.
She said there had been no talk of money or support for the campaign occurred at the lunch.
Under cross-examination, Amanda Banks said she and her husband talked on the way home. She had come to the conclusion that monetary support from Dotcom was unlikely.
The evidence was in contrast to that of Kim Dotcom's wife, Mona Dotcom, who testified she and Amanda Banks were at the lunch table when Kim Dotcom offered a $50,000 donation to John Banks.
SkyCity chief executive Nigel Morrison gave evidence today that Banks received SkyCity's cheque at a short meeting for that express purpose.
Morrison said the company assumed the donation was not going to be anonymous.
Two character witnesses, Remuera financial adviser Marie Quinn and former MP Ian Revell, testified that Banks was scrupulously honest.
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