Key Points:

Former Environment Ministry employee Erin Leigh claims Labour Party activist Clare Curran was hired by the ministry to look after a minister's political agenda.

"I was told she was being employed to look after David Parker's personal political agenda, and I could not work in those circumstances professionally or ethically. As a result of her appointment I resigned. I felt the situation was untenable," Ms Leigh said last night.

There is a long-standing convention that the public service is politically neutral. State Services Commissioner Mark Prebble yesterday reiterated public servants could have political affiliations, as long as they did not bring their jobs into politics or politics into their jobs.

Ms Leigh - who has worked in communications for 20 years and worked for eight different Government departments - had worked on four climate change contracts for the ministry over a year-long period, and then as a subcontractor. Ms Leigh said a permanent position was under discussion, but Ms Curran's appointment meant she could not stay.

"I had never heard of her ... but I made sure I was gone before she started because I didn't want to be tarnished with that. My ethics and my profession are important to me, and my integrity."

Ms Leigh said two senior staff members had convinced her Ms Curran's role would be as a watchdog to ensure Mr Parker's agenda was being "looked after".

"My advice to the ministry at the time was to push back on the minister and that I thought it was possibly illegal. The response of the person I discussed this with, who was a senior member of staff, was that they felt there was no choice."

Ms Leigh said she was under no illusions about the reaction her disclosures would incur, and she expected her personal and professional integrity to be attacked.

"As a person who has worked in communications and PR for so long, and knowing the workings of government so well, I have no doubt in my mind that I will be blacklisted. I did at the time consider making a complaint to the State Services Commission, however I knew the consequences to me personally and professionally were going to be quite profound."

Yesterday, Dr Prebble announced the SSC would hold an inquiry into the circumstances surrounding Ms Curran's appointment. Ms Leigh welcomed the news and said she would happily talk with the inquiry if asked.