A ruling by a High Court judge today means that New Zealand's spy agency will have to reveal details of their secret surveillance of Kim Dotcom. The decision, which will see the Government Communications Security Bureau added to Dotcom’s lawsuit over an illegal January raid on his mansion, means that the GCSB may now be sued for damages after it was revealed the agency illegally spied on him.

When Kim Dotcom warned that the developments surrounding his case would be both big and controversial, the Internet entrepreneur wasn’t exaggerating.

The fallout from the January raid on his Auckland home has been making news every week since and today things stepped up another gear.

As previously reported, in June the police search and seizure raids were deemed to have been carried out illegally after it was revealed they relied on invalid search warrants and were executed with excessive force.

Then following a hearing August it came to light that the Government Communications Security Bureau had been spying on both Kim Dotcom and co-defendant Bram Van der Kolk. This action was also problematic since GCSB may not monitor New Zealand residents. This led the spy agency to concede that it had unlawfully intercepted communications.

And today, following an unprecedented High Court ruling, GCSB will have to reveal details of their secret and apparently unlawful surveillance.

In a 16-page ruling, Justice Helen Winklemann ordered GCSB to be joined as a defendant to

Dotcom’s lawsuit against New Zealand’s Attorney General over the illegal January raid.

The Judge also granted discovery of documents related to the previously secret surveillance operation and said that the GCSB must hand over any information sharing agreements it had with local police and U.S. authorities.

Three police officers were also ordered to provide evidence.

Detective Superintendent Pannett was told to produce an affidavit stating whether he viewed a live feed of the January raids and if so provide details of the source of the feed and the events being filmed.

Detective Inspectors Jones and Wormald were told to file affidavits setting out their dealings in respect of other cameras used.

Dotcom and his co-defendants were also given permission to amend their claim to seek declarations about the legality of GCSB’s actions and, crucially. to seek damages against both the spy agency and the police.

“Lets see about US involvement in illegal GCSB spying on New Zealand residents,” wrote Dotcom on Twitter following the ruling.

“The truth will come out, in court.”