One Nation leader Pauline Hanson, making a cup of coffee while she waited, was less than impressed with the display. Human Rights Commission president Gillian Triggs has endured several fiery Senate hearings. Credit:Andrew Meares "I'm absolutely disgusted," she said. "They're carrying on like bloody children." Such chaos was no surprise to Professor Triggs, however, who has endured a number of fiery exchanges with Coalition senators during her tenure, particularly in the wake of the Human Rights Commission's Forgotten Children report on minors in immigration detention. Senator Macdonald memorably derided the report as "irresponsible, irrelevant and inaccurate" despite having failed to read it. His Queensland colleague Barry O'Sullivan once chimed in with the optimistic observation: "I thought you might like to hear a man's voice."

Thursday's spectacle was replete with Senator Macdonald's regular entreaties to senators - usually female - to "calm down" and "control yourself", and threats of recrimination for failure to comply. Committee chair Ian Macdonald tries to eject other senators from budget estimates on Thursday. Credit:Andrew Meares But the wildest spat arose after conservative warrior Eric Abetz accused Professor Triggs of misplaced priorities for writing "pages and pages" about section 18C of the Racial Discrimination Act but "not one word" about human trafficking. "I'm not sure if that was a question or a rather misinformed comment," Professor Triggs said. Senator Nick McKim argues with committee chair senator Ian Macdonald. Credit:Andrew Meares

The interjections to follow sparked an unbecoming shouting match between senators in which Senator Macdonald attempted to eject Greens senator Nick McKim and silence Labor's Penny Wong and Murray Watt. "You are a tyrant and a dictator," a defiant Senator McKim retorted. "You can't make me leave, mate. I'm not going. What are you going to do about it?" The answer was to suspend proceedings for 20 minutes, delaying a session that was already three hours behind schedule and testing the patience of everyone present. "I'm causing all this trouble," a sheepish Senator Abetz grinned while his colleagues argued outside. Senator Macdonald, who holds the title Father of the Senate as its longest-serving member, returned to admit defeat.

"I've been advised by the clerk that I do not have the power to evict anyone or prevent anyone from asking questions," he lamented. As the afternoon wore on, officials from the Australian Law Reform Commission - having waited their turn all day - were sent to catch their taxpayer-funded flights home after being told "we don't need you anymore". Old coals were raked over: the Queensland University of Technology racial discrimination case, Professor Triggs' speech to a Bob Brown Foundation event and the treatment of women in Australian public life. Senator Brandis, understood to have reached a recommendation on Professor Triggs' imminent replacement, gave few clues about the selection process or who the lucky appointee might be. After two hours of testimony, Professor Triggs was excused, with Labor and Greens senators approaching her to offer their thanks - and apologies - in person.

Asked to confirm it would be her last time appearing before Senate estimates, Professor Triggs said: "I sincerely hope so." Follow us on Facebook