Ten men on trial accused of operating a lucrative and illegal Auckland designer drugs ring admit they were pressing pills and supplying them.

But Ron Mansfield, defence lawyer for the alleged ringleader who has name suppression, told a jury in the High Court at Auckland today the made-to-order drugs were legal at the time.

Arrested as part of police bust Operation Ark, the 10 men each face between two and 53 charges each involving class B and C drugs.

They imported chemicals, pressed pills and supplied them in what the Crown says was a lucrative venture worth millions of dollars involving "analogue controlled drugs", made to match the effects of methamphetamine or ecstasy.


But Mr Mansfield told the jury the chemicals used in the ring's pills were not illegal. If jurors, however, decided they were illegal, the trial evidence would not suggest, as is required for a conviction, the 10 men had knowledge of that.

Mr Mansfield's client ran a legal high business and whenever certain chemical compounds were added to the banned list, the man would stop importing or dealing with them.

"People wanted a product that was lawful but had a mimic or sensation of a controlled drug. Customers wanted to be able to purchase such a product to experience a sensation or effect without risk of arrest," Mr Mansfield said.

"There was no success in a business model doing what others were doing unlawfully namely selling a controlled drug."

Discussions recorded by police between members of the ring would show they thought their product was legal, he said.

Beginning the expected 18-week trial, prosecutor David Johnstone spent more than a day opening the Crown case in what Mr Mansfield said was a "clever and contrived manner".

He said the Crown claimed the men sometimes acted in a covert manner. While they wouldn't deny that, actions such as importing powders hidden in packages bound for a cosmetics business could be explained.

The men didn't want customs officers seizing the chemicals for analysis, as that process could take months, and also wanted to keep secret what was in their pills for competitive reasons.

"There was no knowledge or intent to be involved in any way with a controlled drug," Mr Mansfield said.

The others on trial are Johnny Be Good, Stanley Marshall Alphonsus Leone, Matthew Giordani, George Jeffrey Reed, Grant Oswald Petersen, Kevin Sean Challis, Kelvin Sonny Cress and two other men with name suppression.

The trial continues.