Retirement Commissioner Diane Maxwell has been cleared of any accusations of bullying by the Government's watchdog and will return to work tomorrow.

The report – written by Maria Dew, QC, - came at the request of Commerce Minister Kris Faafoi after two written complaints, in late 2018, were made from two unnamed individuals alleging bullying behaviour by Maxwell.

She has been on leave since December last year while the investigation was underway.

"The investigation found that the benchmark to establish bullying conduct was not met, however conclusions in the Report do raise concerns about the effect on complainants," Faafoi said.

In a statement, Maxwell said she was pleased to be cleared of the accusations and was looking forward to returning to work.

"This has been an incredibly difficult period for me and my family, and I want to thank my partner and children for their enormous support."

The investigation defined bullying as: "unwanted behaviour that you find offensive, intimidating or humiliating."

That behaviour had to have been repeated and had a detrimental effect on your dignity, safety and wellbeing".

The allegations, according to the report, included belittling criticism of employees and their work, as well as incidents of aggressive and isolating behaviour.

The bullying allegations was assessed against the CFFC and WorkSafe NZ definitions of what bullying was.

"Applying these definitions of bullying, this investigation has found that Ms Maxwell has not bullied current or former staff of the Retirement Commissioner."

The investigation also found she had not breached her obligations under the law to ensure "good and safe work conditions" so far as they relate to providing conditions free from workplace bullying.

While the report made a finding of no bullying, it did indicate that some previous staff had difficulty with Maxwell's communication style.

"I have reflected on the points made and will ensure that my communication style is professional, courteous and respectful to all staff."

Faafoi said Maxwell had given him an assurance that her return to work will see her focus on creating this environment and continuing to focus on the important work the Commission has to do to ensure Kiwis are best positioned for their retirement.

"HR policies have been updated at the Commission and specifically, there is a new whistle-blower policy in place

Maxwell agreed to a mitigation plan which includes enhanced monitoring and increased presence of senior Ministry of Business, Innovation and Employment staff in the office.

In total, there were 24 current, and former CFFC employees interviewed in the investigation.

Sixteen former employees who allege they had seen or experienced bullying or inappropriate conduct.

The other eight employees, who are all current CFFC staff, were largely supportive of Maxwell and did not report any bullying or inappropriate behaviour.

In late November, Newsroom revealed allegations of bullying against Maxwell.

There were a number of claims, including a group of senior staff who allegedly wrote a letter to the State Services Commissioner outlining their concerns with her leadership.

Maxwell denied the bullying accusations.

In the 2017/18 financial year, almost half of the Retirement Commission's staff left.

After the accusations of bullying were made, Faafoi said Maxwell's contract would not be renewed, after being the Commissioner for two terms.

"Two terms is a significant commitment and after two terms it is appropriate to go to the market to re-appoint for the next term. This was shared to the Commissioner two weeks ago," he told Newsroom.