Attorney-General George Brandis has defended slugging taxpayers with a whopping legal bill to settle the dual citizenship saga by arguing the case is in the public interest.
Taxpayers will reportedly fork out upwards of $130,000 a day on barristers for each day of the High Court case, with overall costs expected to total more than $2 million.
"It is the practice - and it's been a longstanding practice - that when there is a very important matter of constitutional principle at issue then the commonwealth pays the costs," Senator Brandis said.
The High Court, sitting as the Court of Disputed Returns, will return on Tuesday after holding three days of hearings this week.
Nationals Barnaby Joyce, Fiona Nash and Matt Canavan have argued they ought remain in parliament. So too has crossbench senator Nick Xenophon and One Nation's Malcolm Roberts.
But former Greens senators Scott Ludlam and Larissa Waters argue they were right to resign and say the five others ought follow suit.
Chief Justice Susan Kiefel has noted a decision needs to be handed down as soon as possible, with or without reasons.
