Winston Peters says New Zealand deserves answers over the Kim Dotcom affair as a new extradition appeal begins

The Megaupload accused - Bram Van der Kolk, Kim Dotcom, Mathias Ortmann and Finn Batato.

Deputy Prime Minister Winston Peters insists the public has yet to be told everything it should have been told about the Kim Dotcom's case.

But he's not about to launch an immediate inquiry into those questions now that he is part of the government.

The comments come ahead of a lengthy series of Court of Appeal hearings set to run over the next four weeks.

Dotcom and three others involved in the Megaupload filesharing website were arrested by New Zealand police in a dramatic dawn raid in January 2012 north of Auckland.

The arrests were the key part of a worldwide FBI operation aimed at destroying Megaupload and bringing those who ran it to the United States to face charges of criminal copyright breaches, moneylaundering and running an organised criminal enterprise.

Since then, the Government's lawyers have been trying to extradite Dotcom - and co-accused Matthias Ortmann, Bram van der Kolk and Finn Batato - to the United States where they face decades in jail.

A District Court decision the extradition should go ahead was appealed to the High Court, where it was again upheld.

However, Dotcom and his co-accused gained a substantial win by having the court recognise that there was no such thing as criminal copyright in New Zealand law - but saw the court accept other criminal charges it considered matched the American charges.

Kim and Liz Dotcom on their wedding day last month.

The Court of Appeal hearing is expected to see the four accused argue again that the specific charges cited by the US - copyright - don't apply under New Zealand law and that switching those for other charges would go against what lawmakers intended.

Peters has called for an inquiry as recently as a year ago - not for Dotcom's sake, he has said, but to find the answers New Zealand deserves over the way the raid was run.

"I'm talking about the procedures by which he was raided. There were substantial breaches of the law that occurred. Nobody has taken responsibility for it."

The case has been fraught from the outset with questions about the police use of the elite anti-terrorist squad to carry out the raid and the discovery the highly secretive Government Security Communications Bureau had unlawfully spied on the targets.

Deputy Prime Minister Winston Peters says New Zealand has never had the full truth about the previous government's handling of the Kim Dotcom affair.

Amidst it all, the way the Government handled most aspects of its dealings with Dotcom have caused awkwardness and anguish for politicians and civil servants alike.

Peters said the secret settlement between Dotcom and police, in which police paid a six-figure sum to the accused millionaire, should not stand in the way of getting answers.

"The quality of your observance of the law and fundamental rights can't be bargained away with an out of court settlement.

"It goes to what sort of country you want to be. The fundamental way the agencies acted was wrong."

Peters said he remained disbelieving of the claim by former Prime Minister, Sir John Key, that he knew nothing of Dotcom until the day before the raid when briefed by police.

"I simply don't believe it. He's in the Prime Minister's electorate, already created quite a stir since his arrival, and - given the place he had moved into - it would be of some interest in the electorate."

There were also two visits by Dotcom's staff to Key's electorate office, said Peters.

Internet millionaire Kim Dotcom making submissions to the Intelligence and Security select committee in 2013.

In addition, there were media stories in 2011 about Dotcom moving into the Helensville electorate and a briefing to the Prime Minister's office about the rejection of a bid by the millionaire to buy the so-called Dotcom mansion.

During that period, the GCSB - of which Key was minister - was planning an operation with the police and FBI.

Asked if he would push ahead for an inquiry, Peters said: "I've not addressed that issue right now."

He said it would depend whether there was public appetite for it and if informed observers believed it would be of benefit.

"I was the one trying to ask at the time what was going on in our country. It was a totally unsatisfactory chapter in our history."

He said another factor was the ongoing court process. He said work would need to be done to understand potential restrictions on an inquiry before the judicial process was complete.

Regardless of the Court of Appeal decision, either side is expected to ask the Supreme Court to hear a further appeal. If that fails, the next step in the process would see Justice Minister Andrew Little asked to sign off on extradition.

That, too, is also likely to be challenged through a judicial review application to the High Court.