A Senate hearing erupted into by a fiery exchange between a Labor senator and Turnbull government minister Michaelia Cash about her court order to give evidence over police raids on the Australian Workers Union.
At one stage, Labor senator Murray Watt forced the hearing to adjourn after repeatedly being deemed out of order by chair of the Senate economics committee, Liberal senator Jane Hume.
She felt the AWU matter had nothing to do with the Department of Industry, Innovation and Science, which was under scrutiny at the time.
"Senator Watt is entitled to come here and pull a stunt and that is absolutely fine ... he does tend to make statements that have no factual basis," Senator Cash interjected.
On the resumption of the hearing, the chair said Senator Cash did not have to answer any of the Labor senator's questions if she did not feel they were relevant to the Industry, Innovation and Science portfolio.
Senator Cash said the Labor senator had his media headline, then accused him of running a "protection racket" for Opposition Leader Bill Shorten, a former secretary of the AWU.
Senator Cash is challenging the court order which related to Australian Federal Police raids of the AWU offices in Melbourne and Sydney over a Registered Organisations Commission investigation into a $100,000 donation from the union to activist group GetUp in 2006.
Labor accused the minister of avoiding scrutiny when she did not turn up to a hearing on Wednesday.
Senator Watt quizzed the minister over when she was served the subpoena, its nature, whether she has been interviewed by the AFP and whether she was using taxpayers' money challenging the court order.
She repeatedly took the questions on notice and said she would refer them to the relevant committee.
Asked whether the subpoena would affect her role as a minister, she replied: "Certainly not. I don't think I would have been the first minister to be served with a subpoena."
Senator Watt became so exasperated by the lack of answers, he asked Senator Cash what the time was.
"Will you answer that question?" Senator Watt asked.
"Now you are actually being silly, senator," Senator Cash replied.