Labour leader Chris Hipkins has defended the handling of concerns about MP Shanan Halbert, saying there was no direct communication from the former staff affected.
Hipkins told reporters on Friday the email initially raised with the Labour whips' office said the complainant did not want Halbert alerted to their concerns.
"So the whips did have a conversation with him about his staffing but they did not indicate that there had been a specific concern raised ... the Parliamentary Service were also alerted and they had conversations with the staff in his office to ascertain whether there were any issues there with his current staffing, and no issues were identified through that."
He said he was confident the whips' response was appropriate in the circumstances.
"It wasn't even a complainant, it was a third party who raised the issue with the whips office ... the whips at the time went back and said they didn't feel they could follow up without a complaint or without a direct, you know communication with the people that had raised the concern."
Newshub first reported the complaints on Thursday, saying several former employees had come forward to call Halbert a "manipulative", "scheming", "narcissist" bully.
One talked of feeling "belittled" and "unsafe", another felt "absolutely broken", one felt "intimidated, and another said Halbert treated them "like shit".
Labour's whip at the time Duncan Webb had been alerted to the concerns in August - but at that time there was no process for staff to make anonymous official complaints so it was not taken further.
Hipkins said the first he heard about the matter was when he was approached for comment about the story.
He and Halbert both called for complainants to come forward, now a confidential complaints process exists through the Commissioner for Parliamentary Standards.
In a statement on Thursday, Halbert said he only became aware of the issues through the media report and had good working relationships with staff inside and outside of Parliament.
"Occasionally employment issues arise in any workplace, but I have always done my best to work through those professionally and appropriately sought advice and support where required," Halbert said.
"These issues have only been brought to my attention through the media today. I've never had a formal complaint raised against me.
"If a staff member feels that they were poorly treated then I would like to resolve this by engaging in the process that parliament has set up for dealing with complaints.
"I think it's important for the person that's made allegations anonymously and for me. It's so important that the safety and well-being of all people involved is maintained. That would be the best and fairest way to resolve this."
The former staff had raised their concerns about Halbert with the media after hearing Halbert's criticism of National's Tim van de Molen, who was investigated, censured and stood down from all portfolios after intimidating Halbert at Parliament.
"Certainly there's no place for that sort of ... threatening behaviour or intimidation in Parliament," Halbert said.
Kieran McAnulty, who was whip prior to Webb, said he never heard any concerns about Halbert, and while he had dealt with complaints about other MPs, those had all since been made public.