One of Australia’s most senior public servants has been grilled over his decision to wear a T-shirt depicting an Aboriginal flag and clenched fist during a recent address to his department.

Jim Betts, Secretary of the Department of Infrastructure, Transport, Regional Development, Communications and the Arts, was giving evidence to a Senate estimates committee last week when he was asked whether his choice of apparel indicated a political statement on the Voice referendum.

Nationals Senator Bridget Mckenzie asked Mr Betts whether he had worn a “Black Power” T-shirt during his address.

 “Are you confident that you have abided by the Public Service standards with that impartiality?” she asked.

Mr Betts replied that “I don’t even know what a Black Power T-shirt is” but confirmed he wore a T-shirt with a logo of an Aboriginal flag and a clenched fist.

However, he said it didn’t reflect any party political statement, or any position on the Voice or the referendum.

“Are you suggesting that I have contravened the code of conduct? In that case I would strongly recommend that you make appropriate representations to the Australian Public Service Commissioner … and it will be investigated accordingly,” he said.

Mr Betts said The T-shirt was intended as a symbol of solidarity with the Aboriginal community in Australia and with Aboriginal and Torres Strait Islander staff members in his department.

Senator McKenzie’s party colleague Matthew Canavan said he had learned that some people in the department were “deeply uncomfortable” with Mr Betts’ presentation.

“You’re meant to present as a secretary of the commonwealth government, a non-partisan leader of the public service.

“I don’t think this sort of behaviour is exemplary to those standards of the Australian public servant,” Senator Canavan said.

Mr Betts compared the T-shirt to wearing  a rainbow lanyard, which he was sporting during his evidence to the committee last Monday.

“Let me draw that analogy with wearing a rainbow lanyard,” he said.

“Everybody knows that’s a symbol of solidarity with the LGBTIQ+ community in this country … I am attempting to signal inclusivity and solidarity within my department to a broad span of the Australian community.”

As reported by Government News, APSC guidelines about public servants and the Voice released in April advise public servants to exercise judgement when discussing the Voice privately and to avoid wearing campaign material in the workplace.

The guidelines also state the level of caution to be exercised increases with seniority.

“Generally, the more senior your APS classification, the greater the risk your personal engagement in the referendum might affect public confidence in the APS,” the guidelines say.

The referendum to recognise Aboriginal and Torres Strait Islander peoples in the Constitution by establishing an Aboriginal and Torres Strait Islander Voice will be held between October and December this year.