Conaghan was unimpressed,insisting that the Greens MP had violated the dress code.

“This is not a barbecue. This is question time in the Australian parliament. What next,board shorts and thongs? Maybe a onesie in winter,” he said in a statement following the controversy.

“Some may say that it’s a minor matter to not comply with the dress standard but what it says to many,including me,is that there is little respect for the tradition and history of our parliament.”

According to the official rule book — theHouse of Representatives Practice (7th edition) —the standard of dress in the chamber is a matter for the individual judgment of the member,but “the ultimate discretion rests with the Speaker”.

Indeed,the 1000-page tome documents the evolution of that discretion over the decades. In 1977,the Speaker ruled tailored safari suits without a tie were acceptable,laying the foundation for Ruddock’s camel-coloured number decades later. Earlier rulings dating back to the 1920s permitted members to wear hats,but not when entering or leaving the chamber or while speaking.

In 1999,Speaker Neil Andrew told the chamber that the widely accepted standard of professional dress involved good trousers,a jacket,collar and tie for men and a similar standard of formality for women but he would not rigidly enforce this.

This was endorsed by Speaker David Hawker in 2005,who permitted tieless forays into the chamber in some circumstances,but drew a firm line at “casual wear”.

“However,while I accept that members hurrying to attend a division or quorum will sometimes arrive without a jacket or tie,it is not in keeping with the dignity of the House for members to arrive in casual or sports wear,” he said.

In 2022,hurrying or not,ties are not binding.

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