Justice Winkelmann has ordered that an independent barrister be appointed to review "all items seized for the purpose of identifying irrelevant and privileged material".
She also ordered that the "clones containing only relevant and non-privileged material located on the seized electronic items (the disclosable clones) be created and provided to the United States authorities."
Justice Winkelmann will meet with lawyers on both sides on July 4.
Dotcom's San Francisco-based lawyer Ira Rothken told The Dominion Post he did not know what impact the ruling would have on an extradition hearing due to be held in Auckland on August 6.
"We are pleased the court ruled the US acted illegally by taking the hard drives offshore," he said.
However, when asked whether he believed the US Government would return the illegally seized information, he said: "We will analyse the [US] Government's conduct in light of this ruling."
The police have released the following statement in response to Justice Winkelmann's ruling: "The Police are considering the judgement and are in discussions with Crown Law to determine what further action might be required. Police will not be making any comment on the judgement until that process is complete."
Meanwhile Kim Dotcom has been keeping Twitter followers amused. He has posted the photo of a 'wanted poster' in which he held up a daisy, with the words "Kim Dotcom (mega pirate) underneath. In another tweet he there was a link to a photo of a computer screen with "police line do not cross" tape across it and the words "Excuse me, Can I borrow some scissors?"
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