Director-General of Security Rebecca Kitteridge has launched an investigation into the conduct of some SIS staff after correspondence raised concern about favourable bias towards private investigator Thompson and Clark.

In a letter addressing an Official Information Act response today, Kitteridge said she expected high standards of professionalism and conduct from all New Zealand Security Intelligence Service staff.

"The tone of some of the emails being released to you raise concerns about the standards of professionalism being displayed," Kitteridge wrote.

"In light of this correspondence, I have asked for several matters to be looked into. The emails raise questions in relation to conduct and possible bias in favour of Thompson and Clark. These questions are the subject of an internal investigation.

"I have also asked for our internal processes, policies and guidance to be reviewed to ensure that our (necessary and important) engagement with private sector providers is professional, appropriate and even-handed" Kitteridge wrote.

The emails show Thompson and Clark calling on the SIS' Protective Security Requirements (PSR) team to help present information to companies including Otakaro and Southern Response.

The emails indicate staff knew each other well. In one exchange to arrange a coffee date, the SIS staffer referred to the TCIL staffer as "mate" and once the time and venue was chosen, the Thompson and Clark staffer wrote "9 am will work mate at the Archives - just like old times."

Another email reads "sounds spiffing old chap" from Thompson and Clark.

In June 2016, a TCIL staffer asks the SIS staffer to travel to Christchurch to help explain PSR to Southern Response and Otakaro, the Christchurch rebuild agency that succeeded the Canterbury Earthquake Response Agency.

When the PSR staffer asks who Southern Response is, TCIL responds "Government backed insurer handling a lot of claims in Christchurch post quake and after AMI went bust".

The PSR was set up in the wake of the Ashburton Work and Income shooting.

Minister Responsible for the NZSIS Andrew Little said he had been briefed on the issue.
"As it is an employment matter I have confidence in the Director-General of Security to conduct a thorough internal investigation."

Kitteridge's investigation comes as the Ministry for Primary Industries says it has uncovered evidence of potential serious staff misconduct dating back some years.

"The misconduct was uncovered as part of the preparation of a response to an Official Information Act request for all correspondence between MPI employees and Thompson & Clark Investigations Ltd (TCIL)," the Ministry for Primary Industries (MPI) said in a statement.

State Services Commissioner Peter Hughes today that he had widened an inquiry into the use of Thompson and Clark to cover all state sector agencies.

Hughes said he decided to expand the inquiry after information about other government agencies surfaced.

MPI said the alleged misconduct related to events that occurred some years ago and involved several employees who no longer worked for MPI.

MPI had referred the allegation to the State Services Commission.

"We are working to assist the SSC inquiry and are conducting our own internal inquiry," acting director-general Bryan Wilson said.

"MPI entrusts its people with responsibilities that are bound by a number of legislative frameworks. Our behaviour as state sector employees is also guided by the SSC Code of Conduct and by the Privacy Act.

"We are extremely disappointed to learn that past employees of this organisation potentially breached our code of conduct, our trust, and by proxy the trust that was given to them by the New Zealanders that we serve," he said in a statement.

Hughes said the fresh material that persuaded him to expand the inquiry came to light in Official Information Act requests to MPI and the New Zealand Security Intelligence Service.

"What I have seen raises serious questions about the nature of engagement between Thompson and Clark and state sector agencies," Hughes said in a statement.

"As a result I have decided to widen the terms of reference to cover all state services agencies.

"I need assurance that the use of, or contact with, external security consultants by government agencies is consistent with the State Services Code of Conduct."

Hughes appointed Doug Martin in March to investigate the use of Thompson and Clark and other security firms by Southern Response.

Martin is looking into whether the Southern Response agency, set up to settle quake insurance claims, spied on claimants.

That inquiry was expanded shortly afterwards to include the Ministry of Business, Innovation and Employment's (MBIE's) relationship with Thompson and Clark. Activist groups say they have been spied on by Thompson and Clark for MBIE.

The Ministry of Foreign Affairs and the Department of Conservation have also used Thompson and Clark in the past.

Hughes has also appointed high-profile Auckland barrister Simon Mount QC to the investigation team.

Prime Minister Jacinda Ardern has previously described Southern Response's use of Thompson and Clark as "inappropriate" and warned other government departments not to use them in the same way.