The American government's bid to extradite copyright infringement king Kim Dotcom to the United States was dealt a body blow Thursday, when a New Zealand High Court judge ruled that the raids on Doctom's home earlier this year were "illegal." The decision may doom the entire prosecution of the founder of the file-sharing site Megaupload; New Zealand authorities are appealing.

Justice Helen Winkelmann says that warrants for the raids "fell well short of" describing the offenses they were meant to relate. According to Justice Winkelmann, words such as "breach of copyright" used in the warrants do not provide details of the alleged offense and therefore, the warrants do not comply with New Zealand law.

Further undermining the prosecution’s case, Justice Winkelmann also ruled that the FBI’s act of sending clones of Dotcom's hard drives to the U.S. was also unlawful.

The images were sent to the United States despite an agreement with Dotcom's lawyers that it wouldn’t happen before a court hearing on whether or not it was permissible had taken place.

Justice Winkelmann has ordered the FBI to start copying the cloned images in preparation of a potential return to Dotcom. The data on the cloned hard drives amounts to 150 terabytes, and came from 135 computers seized when police conducted an armed dawn raid on his rented home in Coatesville, north of New Zealand’s largest city Auckland.

Labelling the police conduct “an unreasonable search and seizure," Justice Winkelmann found that the New Zealand law enforcers had exceeded their legal authority by continuing to hold material that they themselves had deemed irrelevant to the case.

New Zeland police wanted the FBI to sort the evidence in the United States but this is "an approach not available to them,” Justice Winkelmann ruled.

She ordered the return from New Zealand police and the FBI of all seized assets not relevant to the case and that no further material to be shipped to America without the court’s consent.

The judgement represents a major victory for Dotcom’s legal team and puts the U.S. case against the Megaupload founder and associates in jeopardy.

According to intellectual property lawyer Rick Shera, Justice Winkelmann’s ruling is a "body blow to the prosecution – not just in New Zealand but in the United States as well."

A follow-up hearing is due on July 4 that will decide how the Megaupload case will proceed given the illegal searches and warrants. Shera says that a successful hearing for Dotcom could mean the case won’t continue due to the amount of inadmissible evidence.

However, Dotcom’s legal team has its work cut out for them still. An appeal against Justice Winkelmann’s ruling is likely, Shera says, due to the adverse consequences for the prosecution.

New Zealand police issued a curt statement saying it is considering the judgement and are in discussions with Crown Law to determine what further action might be required.

Full text of Justice Winkelmann’s ruling below.

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