The director of private investigation firm Thompson and Clark bought psychoactive substances including synthetic cannabis on behalf of the Ministry of Health, the ministry has revealed.
Staff from the company also visited shops to make sure they weren't selling illegal high-powered laser pointers.
The ministry confirmed Thompson and Clark director Gavin Clark visited shops selling psychoactive substances to ensure they were complying with the Psychoactive Substances Act and "at times making controlled purchases of products such as synthetic cannabis".
The bulk of the work carried out by Thompson and Clark had been monitoring retailers to ensure they were complying with regulations restricting the sale and supply of high-powered laser pointers (HPLPs), the ministry said in a statement.
The pointers have been used in the past to blind pilots in the cockpits of planes coming in to land.
"This work has involved visiting retailers in the Northland and Auckland regions to identify if there were non-complying HPLPs for sale. [Thompson and Clark] also regularly monitored the internet to identify if there were non-complying HPLPs for sale," the ministry said.
The Ministry of Health is one of a number of government agencies that have used the Auckland-based company, which is at the centre of a probe by the State Services Commission.
The ministry said it had a one–year contract with the company, capped at $70,000 excluding GST. The contract ends in 10 days on June 30.
A spokesperson for the Ministry of Health said it supported the SSC's inquiry and continued to provide updates which might fall under the new broadened scope of the commission's inquiry.
"It's important to note that Thompson and Clark Investigations Limited is identified as an approved whole of government provider of services," the spokesperson said.
State Services Minister Chris Hipkins said today the SSC probe would look into why Thompson and Clark was still listed as an all of government contractor on the New Zealand Government Procurement website.
"That's one of the things I know the investigation is going to be looking at," Hipkins told reporters.
"Once somebody's on that list there has to be a very good reason to take them off which means there has to be a very good legal case and that is what the investigation will be exploring."
Hipkins said Prime Minister Jacinda Ardern and he had been very clear the firm should not be used by government agencies.
"I think that would be a unwise course of action for any government agency to be taking at the moment. The Government has made its expectations very, very clear."
Deputy Prime Minister Winston Peters said he was not aware of any agencies still using Thompson and Clark.
He said it was a serious concern that state agencies would deal with private contractors in that way.
State Services Commissioner Peter Hughes has widened the inquiry into the use of Thompson and Clark to cover all state sector agencies after new information surfaced implicating the New Zealand Security Intelligence Service (NZSIS) and Ministry for Primary Industries (MPI).
Agriculture Minister Damien O'Connor welcomed the investigation.
"Sunlight is the best disinfectant and I'm sure the State Services Commission going to do their job properly."
Thompson and Clark director Gavin Clark said the company was willing to co-operate fully with the SSC and would wait for the investigation to take its course.
"Thompson and Clark abide by the laws of NZ and adhere to the industry standards and code of conduct," he said in a statement.