Australia's largest airline, Qantas, has lost its high court case to overturn a prior ruling in July 2021 that said it has illegally outsourced 1,700 ground hander jobs.

Australia's high court has unanimously upheld a full federal court decision forcing the airline to compensate workers it fired at 10 airports back in November 2020.

Qantas' decision to lay off its staff also happens to be "the largest sacking found to be illegal" in Australia's history, Transport Workers' Union (TWU) National Secretary Micheal Kaine told reporters in Canberra. He added that the Union will look to gain "significant" compensation and penalties against Qantas in federal court.

TWU called on Qantas for a public apology and for its chairperson, Richard Goyder, and the entire board to be replaced by new executives, which would include a worker representative.

Previously, Australia's federal court ruled that Qantas' outsourcing of workers was in violation of the Fair Work Act as the company aimed to bypass industrial action. The ruling was considered a major victory for TWU and workplace relations minister Tony Burke who supported the case.

Just before the high court made its ruling, Kaine said Qantas' actions were driven by its outgoing chief executive Alan Joyce's "spiteful management style."

"Qantas workers have made history today. It has been three years and 20 days since Alan Joyce first announced the decision to outsource these workers, and they have not stopped fighting for a moment to ensure justice was served," Kaine said in response to the court's decision.

"The final act of this board should be to strip Alan Joyce of his bonuses and follow him out the door," the Union leader proclaimed.

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Kaine said it is necessary that the airline change its board for its survival, as "the same board that resided over the largest case of illegal sackings in Australian corporate history" cannot be the same board that achieves the necessary reset.

The high court stressed that although Qantas "had sound commercial reasons for the outsourcing decision," the decision was taken "to prevent the affected employees from exercising workplace rights to organize and engage in protected industrial action and to participate in bargaining."

Qantas had claimed that outsourcing was due to financial measures that could save it $100 million annually and reduce future spending.

"As we have said from the beginning, we deeply regret the personal impact the outsourcing decision had on all those affected and we sincerely apologize for that," a statement from Qantas read.

Qantas has faced intense criticism for its handling of flight credits accumulated during the pandemic, leading to a class-action lawsuit. Additionally, there are allegations of flight cancellations aimed at securing slots at major airports, with the competition regulator seeking penalties amounting to $600 million.

McManus and Kaine have called upon the Senate crossbench to support Labor's industrial relations bill aimed at closing loopholes. McManus contends that this bill could potentially prevent layoffs at their root by mandating equal pay for labor-hire entity workers compared to those covered by workplace pay agreements.

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