The man, who cannot be named for legal reasons, was involved in a family law financial matter in the Federal Circuit Court in 2018. Self-represented, and unable to hand over the information he was required to, the man was jailed by Vasta and claims to have then been abused in custody.

Within months, the Full Court of the Family Court set aside Vasta’s orders and described his treatment of the man as a “gross miscarriage of justice” lacking in procedural fairness.

While judges traditionally have judicial immunity, and normally cannot be sued, the man took action against Vasta in the Federal Court using a precedent that lower level courts may be exposed if they go beyond their jurisdiction.

The case, which also names the Queensland Government as a defendant, is being keenly monitored by legal observers and has already attracted significant media attention in specialist law publications.

Vasta has not filed a defence but the Commonwealth has now sided with the judge.

The Commonwealth, in its defence, accepted that Vasta failed to accord the man procedural fairness. But it argued the judge was still afforded immunity from lawsuits due to his role and that of the court.

While the Federal Circuit Court was not specifically designated a “superior” court under legislation, the powers it wielded put it in that category – including, in this case, the ability to punish a contempt of court.

The government accepted Vasta failed to afford the man procedural fairness but said “immunity is not lost because the judge, in a matter within jurisdiction, makes an order which the Court has power make, even if, in making that order, the judge failed to comply with mandatory conditions and thereby acted contrary to law”.

In defence of court security officers, who were unexpectedly called on to detain the man, the government argued “a person is not liable for false imprisonment if the person detains another person in the course of executing an apparently valid order made in the exercise of judicial power”.

In any event, the government did not accept the man “suffered loss and damage in the nature of psychiatric injury, pecuniary loss and loss earnings/earning capacity by reason of the imprisonment”. It left Vasta to respond to other allegations.

The case is due back in court, before Justice Michael Wigney, next month.

Vasta’s controversial decisions and courtroom behaviour have drawn attention in recent years, sparking a debate about judicial accountability.

He comes from a high-profile family: brother Ross is a federal Liberal MP, while their father Angelo Vasta, a former Supreme Court judge in Queensland, remains the only judge since Federation to have been removed from office by an act of parliament. Vasta’s wife Deborah is a serving Queensland magistrate.