Another High Court challenge is being flagged against the constitutional right of the Queensland government to keep the state's borders closed.
School students, workers and freight drivers can enter the state without an issue, but Queensland is closed to anyone else because of the COVID-19 pandemic.
"We are arguing that the Queensland government did not have the constitutional right to shut the border," Mahoneys litigation partner Mitchell Downes said in a statement on the firm's website.
He said the move was part of a wider effort to help Queensland's tourism industry recover from the effects that COVID-19 had had on the industry and businesses and people that rely on it.
A gofundme page has been set up to fund the challenge and allow the plaintiffs to start the case in the High Court "as soon as possible".
The Australian reported the challenge had been lodged on Monday, with six plaintiffs including a Brisbane travel agency and a Cairns charter operator, plus interstate individuals and a company.
One Nation leader Pauline Hanson has also threatened legal action in the High Court if borders aren't reopened.
Premier Annastacia Palaszczuk has refused to buckle to pressure to reverse her decision to keep the borders closed during the coronavirus crisis.
She has flagged a potential September re-opening, however this is under a monthly review and could be pushed forward.
Tourism operators across the state will rally on Tuesday to plead for a firm date that will allow them to prepare to reopen, and for interstate customers to properly plan their trips to the Sunshine State.
"We don't actually need them to open tomorrow," Greg Daven from Gold Coast and Cairns ballooning operator Hot Air told the ABC.
"We're just calling on the premier to give us a date so we can start planning and our customers who are dreaming in NSW and Victoria of coming on a Queensland holiday can actually turn that into a reality."
He and other tourism operators are bringing vehicles of all sorts - from hot air balloons and jet skis to cars and caravans - to the rally at The Spit on the Gold Coast.
Similar gatherings, called Toot for Tourism, are being held in Airlie Beach and Cairns.
Mr Daven said many operators have had zero income since the border lockdown in March, and that his business had laid off around three-quarters of its 80-strong staff.
He said the industry risks losing $500 million if the borders stay shut until September.
"We do need to get our borders back open again, otherwise we run the real chance that if the trans-Tasman bubble happens ... we could actually see Australians travelling to New Zealand before they can come to Queensland and that wouldn't be a good look for the industry and we could have catastrophic results," he said.
Australian Associated Press