The Transport Minister has refused to order an investigation into whether an "incredibly manipulative" fraudster was able to restructure attempted whistleblowers out of the ministry.
For three years Ministry of Transport staff raised concerns about Joanne Harrison's conduct and the lack of contracts and documentation surrounding the deals she was signing.
The chief executive at the time, Martin Matthews, repeatedly gave Harrison the benefit of the doubt.
It wasn't until 2016 that Harrison was finally caught out by an external audit - in that time she'd stolen $723,000.
In February she was sentenced to three and a half years in prison.
Labour's Sue Moroney said three staff complained about Harrison in October 2015, and were then all made redundant just two months later.
During Question Time at Parliament yesterday Ms Moroney asked Transport Minister Simon Bridges whether he'd make sure they'd been treated fairly.
"Will he order an investigation to ensure that staff who raised concerns about Joanne Harrison's financial transactions and were subsequently made redundant in a restructuring influenced by Joanne Harrison were treated fairly by his ministry?"
Mr Bridges responded that any investigation "is a matter for the ministry" - it has already refused to investigate.
"What is now very clear from public interviews, from the select committee ... and other documentary evidence as well is that the person in question here was not involved in the decision making process in the restructure," Mr Bridges said.
Ms Moroney asked how the fraud could possibly have happened.
"How did a person convicted of fraud in New Zealand, also under investigation for fraud in Australia, get employed by his ministry to a senior management role?"
Mr Bridges responded that the answer to that question was "very simple".
"She was incredibly manipulative, dishonest person who has now gone to jail for some time.
"That is not to say that there weren't very significant lessons that the ministry could - and I am satisfied has - learnt from that," Mr Bridges said.
Documents relating to the fraud made public by the Transport Ministry show that over three years Harrison frequently signed deals with no contracts in place and exceeded her authorised spending limits.
The documents show Mr Matthews, was repeatedly told about this by the ministry's finance and legal teams.