Parliament House security has confirmed it asked a man to turn his singlet inside out before entering the building because it featured an Aboriginal flag with the words "White Australia has a black history".
The story was submitted to Reddit on Wednesday, with user Angrydave writing he was a friend of the man who was told the singlet was, "a form of protest." The pair were also told Parliament House security "do not allow any form of protest inside Parliament House."
The day's original purpose was to see how many Canberra institutions the pair and several friends could enter wearing thongs and singlets.
"We all turned up in thongs and T-Shirts, and our colleague was singled out by security. A senior security officer was radioed down to the security checkpoint and he was told, in no uncertain terms, that if he didn't turn his shirt inside out that he would be refused entry. He reluctantly agreed. Everywhere else we went that day (National Library, etc) didn't bat an eyelid," he wrote.
"Protest paraphernalia including banners, placards and clothing with specific messages are not permitted into Parliament House," a spokesperson for Parliament House told BuzzFeed News.
"Protest paraphernalia can take many forms and therefore it is not possible to be totally prescriptive as to what is or is not acceptable. Security Officers have exercised discretion in good faith and the Department of Parliamentary Services regrets if any offence was taken by the individual."