The UK government spent almost £1.2m ($1.5m) of taxpayers' money on legal fees to fight Gina Miller in the Article 50 court battle, documents released by the Department for Exiting the EU (DexEU) show.
The accounts published on Wednesday (19 July), just a day before parliament splits up for the summer recess, showed David Davis' ministry spent £317,000 on legal fees, £333,000 on other counsel fees and £493,000 to the victorious parties.
Around £78,000 was also spent on a separate legal fight concerning Article 127 of the European Economic Area, with a victory for the government in the House Court.
But Theresa May lost the Article 50 case in the High Court and Supreme Court. The rulings meant MPs and peers had a say on triggering the UK's split from the EU.
The bill passed through parliament and Sir Tim Barrow, the UK's chief representative to the EU, hand-delivered the exit notification to EU Council President Donald Tusk.
"The Conservatives fought every step of the way in the courts to try and avoid proper scrutiny over Brexit. Now the public is having to pick up the tab," said Liberal Democrat Brexit spokesman Tom Brake.
"None of this would have happened if the government had done the right thing and given parliament a full role from the start. But this bill is nothing compared to the huge cost the country will pay if the Conservatives plough ahead with their extreme version of Brexit."
A spokesperson for DexEU said: "The Article 50 court case raised a vital issue relating to the UK's constitutional arrangements. The government thought it was right to bring the case to the UK's highest court."