One in 12 people employed at Parliament House have reported feeling bullied and harassed at work, but no follow-up has occurred.
The findings were outlined in a staff survey conducted by the Department of Parliamentary Services.
The department is responsible for a broad range of operations including security, food and beverage outlets, libraries and technical support.
Greens senator Larissa Waters quizzed the head of the Department of Parliamentary Services about the staff survey during a public hearing on Monday.
"Can you explain to me why the eight per cent of staff that reported … did not receive an investigation into their concerns?" she asked.
Department secretary Robert Stefanic said there was a difference between an anonymous survey and formal reports of workplace abuse.
"The survey is something that people report, I guess, in terms of their perception of whether they have been bullied or harassed," Mr Stefanic said.
He said the confidential nature of the survey meant the department had no way of knowing who had experienced bullying or harassment, and no evidence to launch an investigation.
Senator Waters suggested cultural issues might prevent staff from making formal complaints, despite various reviews and reports into the workplace culture at parliament.
"That rings alarm bells for me," Senator Waters said, requesting more information from the department.
Steven Fox, the parliamentary librarian, said he believed the department had a positive culture and noted the 2022 survey was more than a year old.
He said it might not reflect the contemporary experience of staff.
The next staff survey is planned for May 2024.
A major report titled "Set the Standard" was published in 2022 following widespread reports of harassment, sexual assault and bullying at Parliament House.
Since then, 13 of the report's 28 recommendations have been implemented.
An independent parliamentary standards committee will be established by October, after being delayed for more than a year.
Senator Waters said the body was needed immediately.
"Without this body, bad behaviour continues to go unchecked, we know that without real prospects that an MP will be sanctioned, staff are reluctant to come forward, consequences are crucial," she said.
