Billionaire Anthony Pratt, who donated $1.5m to the Liberal Party in 2019-20, and Prime Minister Scott Morrison (Image: AAP/Mick Tsikas)

Never before have the world's richest people been so exposed for how little tax they pay.

But the revelations this month from US investigative journalism outlet ProPublica (republished in Crikey) about the scandalously low tax bills of American billionaires may unfortunately be a one-off. The story was only possible after a leak from inside the US tax office, the Internal Revenue Services (IRS).

So any hopes of working out how much or how little Australia’s powerful billionaires pay relies on someone inside the Australian Taxation Office (ATO) leaking the same information. And given the experience of ATO whistleblower Richard Boyle, who faces a lifetime in jail for exposing its debt collection tactics, that is incredibly unlikely.