The High Court has found the sacking of nearly 1700 Qantas staff was illegal – dismissing the airline’s appeal in a judgment released on Wednesday morning.

The airline had appealed two rulings by the Federal Court, which found the outsourcing of work done by baggage handlers, cleaners and ground staff – and their mass sacking during the COVID pandemic – at 10 airports was illegal.

After the High Court’s unanimous ruling on Wednesday, Transport Workers Union National Secretary Michael Kaine said the mass sacking was a “reprehensible act”.

“[This is] a massive victory in the workers in the highest court of the land. The court has dismissed unanimously Qantas’s appeal … Their action against these Qantas families, as the largest sacking in Australian corporate history, has been found to be illegal,” he said.

“These workers have been through hell and back, and today, there are smiles on their faces because it’s been three years of hell for their families and now, justice has prevailed.”

The TWU wants workers reinstated and Qantas fined. Kaine also urged Qantas board chairman Richard Goyder to follow recently departed former chief executive Alan Joyce out the door.

“There are serious consequences that should flow from this. Richard Goyder and the board should go. Richard Goyder and the board have been complicit in this illegal sacking of 1700 workers,” he said.

“On numerous occasions, Richard Goyder backed in Alan Joyce in relation to this very decision … This has been a spiteful dictatorship and the board has been right behind Alan Joyce.

“But their last act before they walk out the door should be to rip away from Alan Joyce the obscene bonuses that he has taken as these families suffer. The bonuses have to go, the board has to go.”

Kaine also urged the government to quickly passed its workplace reform bill, which will no longer allow businesses to use outsourcing to undercut agreed pay and conditions.

“The loopholes bill is designed to close the loophole Alan Joyce and his management team have opened over a period of 15 years. It is now urgent,” he said.

In a brief statement, Qantas said it acknowledged and accepted the High Court’s decision to uphold the earlier ruling by the Federal Court.

“Qantas has said from the beginning we deeply regret the personal impact the outsourcing decision had on all of those affected and we sincerely apologise for that,” it said.

Earlier, the airline was found to have breached the Fair Work Act in its 2020 decision to outsource its ground operations to avoid enterprise bargaining rights, after the TWU took legal action.

The airline lost billions of dollars due to the pandemic, which decimated the aviation sector.

In May, Justin Gleeson SC for Qantas, told the High Court that Qantas’s revenue stream had been shattered by the pandemic, which left it “bleeding cash”.

But the airline has since posted an underlying profit of almost $2.5 billion for the past financial year.

Qantas argued it could not have breached the workplace rights of the employees, as they did not have the right to take protected industrial action at the time of the decision to outsource.

Workplace Relations Minister Tony Burke has intervened in the case.

-with AAP