DEMOCRATS leader Andrew Bartlett mauled a female Liberal senator and hurled abuse at her during a late-night fracas over stolen wine.
A shaken Senator Jeannie Ferris was left nursing an injured upper arm after chasing Senator Bartlett, who had taken five bottles of wine from a Liberal Party Christmas barbecue in Parliament House.
The ugly altercation spilled on to the floor of the Senate chamber, where Senator Bartlett repeatedly shook Senator Ferris by the shoulder and called her a "f...ing bitch".
Senators, including fellow Democrat Lyn Allison, watched in horror as the purple-shirted and purple-faced party leader lurched at Senator Ferris, grabbed her then hurled abuse.
Senator Ferris was deeply upset by the Thursday night incident and yesterday said her arm still ached badly.
Burly Senator Bartlett, 39, a former champion rugby player, apologised in person and in writing yesterday.
He has campaigned against violence to women.
Senator Ferris was prepared to let the matter rest until Senator Bartlett apologetically sent a card yesterday and a single bottle of wine wishing her a "relaxing break".
Senator Ferris wrote back, urging the Democrats leader to seek a "treatment program".
"There is no doubt in my mind that you were seriously under the influence of alcohol and perhaps you should consider whether a treatment program could assist you," she said in the letter, which was also sent to Senate President Paul Calvert.
"Whilst I said to you this morning that I accept your apology and I do my arm remains quite sore, and I continue to be deeply offended by your behaviour.
"You clearly intended to intimidate me and were obviously angry because I had sought the return of five bottles of wine that you had taken to your office from the Coalition Christmas barbecue.
"You grabbed my arm with considerable strength and called me a `f...ing bitch' several times. When I asked you to let go of me and tried to walk away from you, you followed me continuing to call me a "f...ing bitch".
Senator Ferris hosted the Coalition Christmas Party and had welcomed Senator Bartlett as an unexpected guest and did not object to him joining the drinking.
But Senator Ferris decided enough was enough when she spotted the Democrats leader hightailing from the party, arms full of wine.
Liberal staff were despatched to retrieve the five bottles, but it is understood they returned with only four.
When a Senate division was called later in the night, Senators Ferris and Bartlett came face to face on the floor of the chamber and the angry confrontation ensued.
Footage of the proceedings did not pick up the incident but showed a stunned Senator Allison watching in horror.
Senator Bartlett then came into video view as he staggered across the chamber.
A spokeswoman for Senator Bartlett last night said the Democrats leader regretted his behaviour.
"Senator Bartlett said he regretted his comments to Senator Ferris and any aggressive behaviour." she said.
"He has apologised in person and in writing yesterday morning."
Senator Bartlett has built a career in public life on compassion towards animals and has been a strident campaigner on women's issues.
He lashed the Federal Government for cutting funding for domestic violence programs during his Budget reply in May.
And he highlighted the role of domestic violence in homelessness at a Democrats youth conference in July, at which he also spoke of the dangers of teenage binge drinking.
Before entering Parliament in 1997, he spoke on behalf of Men Against Sexual Assault at a rally against domestic violence in Brisbane.
Preventing violence against women has been a key theme for the Democrats. Senator Bartlett's predecessor, Natasha Stott Despoja, spoke on the issue just 12 months ago in Parliament.
Andrew Bartlett played for a champion team while representing Queensland in under-16s rugby union.
"In those days . . . he was capable of physical exertion," his biography on the Democrats website states.