There were claims of a "cut-and-paste" judgment lying behind a court's endorsement of the extradition of Kim Dotcom and others to the United States to answer allegations of massive copyright infringement through the defunct Megaupload website.
The Supreme Court has been told the decision at the North Shore District Court was flawed because the judge hearing the initial extradition request did not properly assess the case against Dotcom, Matthias Ortmann, Bram van der Kolk and Finn Batato.
Grant Illingworth QC said "His Honour cut and pasted 150 pages of the US submissions" into the judgment which found the accused were eligible for extradition.
The claim from Illingworth was among arguments put before the Supreme Court in his bid to have the extradition order overturned for his clients, Ortmann and van der Kolk, and their co-accused.
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The Supreme Court is hearing a final plea from Dotcom and three Megaupload executives to reject a court ruling they must be extradited to the United States to face allegations of massive copyright infringement.
The United States has sought their extradition, alleging the copyright abuse through Megaupload - which was taken down in 2012 - cost movie and music producers US$500m.
Dotcom, Matthias Ortmann, Bram van der Kolk and Finn Batato have all denied any wrongdoing. Of the four, Dotcom was the sole defendant absent from court today. His wife Liz Dotcom was present as a member of his legal team.
The Megaupload four were arrested in January 2012 as part of a worldwide FBI operation which saw simultaneous raids targeting bank accounts, data and seven people across the globe.
Illingworth invited the Supreme Court to walk across one of four planks to reach a point where they would overturn the extradition decision made by Judge Nevin Dawson in 2015, since upheld at the High Court and Court of Appeal.
The "cut-and-paste" allegation went to Illingworth's argument - also advanced by lawyers for the others - that there should have been a judicial review of the extradition agreement at the High Court.
The High Court rejected the request for a judicial review, saying it could deal with the issues as part of the appeal against the judgment.
The difference was said to be the High Court's acceptance of the assessment of the US case against the accused, rather than examining whether it had been properly assessed in the first place.
Illingworth said he had a copy of the extradition judgment with sections highlighted to show how much matched - or closely resembled - the US submissions.
He said the High Court should have allowed a judicial review which studied alleged flaws in the extradition judgment which would have exposed "invalidating deficiencies".
An airing of the same argument struggled at the Court of Appeal against the Crown's argument it made no difference,
The other arguments put to the Supreme Court this morning saw Illingworth argue that copyright as alleged against the Megaupload defendants was "not criminal here". He said the law required extradition to be based on offences which were crimes in both the country seeking extradition and the country which received the request.
Illingworth said the Supreme Court also needed to consider the need for the requesting country to show there was enough evidence to justify a prosecution.
He said there had not been sufficient evidence put forward to warrant that with the US not showing, for example, evidence of who owned the works alleged to have been pirated, or how they had been illegally copied.
Illingworth said the law had been so seriously misapplied by the district-court decision it created a "serious miscarriage of justice". He said it should not have been confirmed by higher courts and asked the Supreme Court to reject it.
The Supreme Court justices hearing the case are Chief Justice Helen Winkelmann, Justice Susan Glazebrook, Justice Ellen France, Justice Mark O'Regan and Justice Joe Williams.