The senior police officer under fire for the raid on Kim Dotcom's home headed another controversial operation which saw a court fooled into prosecuting an undercover cop.
Detective Inspector Grant Wormald was in charge of Operation Explorer to infiltrate the Red Devil motorcycle gang.
But a judge is now deciding whether to throw out the case, or if evidence gathered after the staged prosecution is admissible in court.
The Crown case against 21 people arrested in the operation is understood to rely heavily on that evidence.
Mr Wormald also supervised the joint FBI-police raid on Dotcom's Coatesville home for the Organised and Financial Crime Agency. He is facing allegations he lied under oath about illegal spying on the German millionaire.
In a court hearing last month Dotcom's lawyer, Paul Davison, accused Mr Wormald of giving "inconsistent" testimony about surveillance by Government Communications Security Bureau (GCSB) on behalf of police.
Mr Wormald had told the court no other agency had been involved in the spying - but it has since emerged GCSB was illegally monitoring communications from Dotcom and his co-accused, Bram van der Kolk, for a month before his January 20 arrest. Dotcom's legal team have indicated they will lay a complaint with the Independent Police Conduct Authority.
In the Red Devils case, an undercover cop using the name Michael Wiremu Wilson infiltrated the gang and police orchestrated the false arrest to boost his criminal credentials.
Lawyers for the defendants have argued the prosecution was an abuse of the court process and want charges - which include drugs, firearms and conspiracy to take part in an organised group offences - thrown out. A lawyer with knowledge of the case said the court must decide if the ends justified the means and could stop the prosecution in its tracks.
"There's a disturbing similarity between this case and the Dotcom fiasco in terms of the police investigating in a manner that is outside of the law," he said.
Justice Simon France reserved his decision in August and is expected to make a ruling soon.
"Wilson" was charged with possessing equipment to cultivate cannabis in May 2010.
He also twice failed to appear in court to enhance his standing with gang members and warrants were issued for his arrest. The charges were eventually withdrawn when the operation ended in March 2011.
Police sought the permission of then Chief District Court (the late) Judge Russell Johnson after the arrest, the Nelson District Court was told in July.
Court staff, the judges he appeared before and some police officers did not know the arrest was a fake. However, police have argued the hoax was necessary as "Wilson" was threatened by a gang member.
A spokeswoman said because the case is still before the court police were unable to comment. "Detective Inspector Wormald was the officer in charge of the investigation but was not a decision-maker in regard to the arrest and prosecution of Mr Wilson," she said. However, in an affidavit to the court, Mr Wormald said he was frequently briefed by the undercover agent's "operator."
"I have also been party to any decision made in relation to the continued deployment of the Special Duties Constables [undercover officers] and any action that is taken."
- Fairfax Media