"This lost revenue means millions of dollars' worth of public services go down the drain. Malcolm Turnbull has ruled out negative gearing changes in the budget on May 3. Credit:Alex Ellinghausen "When wealthy people are allowed to hide money offshore, we all suffer: our schools are forced to rely on the charity of parents to buy the equipment they need to teach our kids, our hospitals have to turn their back on people in need of beds, homeless youth and family violence victims can't get help, people without paid work have to survive on just $37 a day and we will struggle to transition to a world with zero carbon pollution." In October last year, Mr Turnbull was attacked under parliamentary privilege over his personal investments in a number of Wall Street hedge funds based in Caribbean tax havens, including two registered at a Cayman Islands address that was once described by US President Barack Obama as "the biggest tax scam on record". Labor was accused of stooping to the "politics of envy" in response.

The open letter urges Mr Turnbull to outlaw the use of shell companies with concealed ownership and other means of tax avoidance, exposed comprehensively in the Panama Papers leak. "You can require multinational companies to be transparent about their activities, so that they can't avoid their tax obligations. You can scrap secrecy laws that allow accountants and lawyers to help their clients siphon away public money," the letter states. The Panama Papers and Australia's response to it will take centre stage on Thursday when Tax Commissioner Chris Jordan fronts a specially-convened hearing of the Senate inquiry into tax avoidance. Mr Jordan, who returns this week from Europe where he is trying to lead a global response to the Panama Papers, will be asked what extra powers the ATO and government agencies need to stop money being stashed in tax havens.

Senator Sam Dastyari, a committee member, said: "Frankly – saying enough is being done already doesn't cut the mustard. We need to give the Tax Office the powers it needs to change the game." "Everyone is fed up with a handful of companies and individuals taking the rest of us for a ride. "It's time we put some tough action on the table. I'll be asking the tax commissioner if we need to overhaul our legal system and if we need to start arming him with extra-territorial powers. "Some of these companies are shifting money like the mob. With the left hand pretending it has no knowledge of what the right hand is doing." On Wednesday, the US Department of Justice said it had launched a criminal investigation into international tax avoidance schemes exposed by the Panama Papers leak.