The federal Labor MP Mike Kelly, who represents the bellwether NSW seat of Eden-Monaro, faces a legal bill ''in excess of $100,000'' after the High Court ruled against his application to have a defamation suit against him struck out, although he insists the bill does not put him at risk of bankruptcy and exclusion from Parliament.
Dr Kelly is being sued for defamation over a tweet in 2011 accusing the Liberal pollsters Linton Crosby and Mark Textor of ''push polling''.
Using his MP Twitter account, the former Australian army lawyer tweeted: ''always grate [sic] to hear moralizing from Crosby, Textor, Steal and Gnash. The mob who introduced push polling to Aus.''
Mr Crosby and Mr Textor launched defamation proceedings, which Dr Kelly sought to have struck out on the basis that the Federal Court had no jurisdiction to deal with the case.
But the full Federal Court rejected the claim and awarded costs against him, whereupon Dr Kelly, recently promoted to Minister for Defence Materiel, applied for special leave to have the matter heard by the High Court. Ten barristers travelled to Canberra to argue the complex jurisdictional point on Friday.
But the court knocked back the case without even hearing from defence counsel.
Taxpayers will foot the legal bill for the Commonwealth, ACT and Northern Territory governments, which were also joined as parties to the dispute.
Together those governments had six barristers at Friday's High Court hearing.
Dr Kelly told Fairfax Media the NSW Labor Party had already put $20,000 towards his legal costs, but the party would not pay any more.
Last year he said: ''In these circumstances it was appropriate to get some support … I am not a rich person, I am not Clive Palmer or Gina Rinehart.''
In his new portfolio as Minister for Defence Materiel, Dr Kelly receives a salary of $300,116. According to the register of parliamentary interests, he and his wife have a mortgage over a home in Karabar, NSW.
His only other assets are an ANZ savings account and the car he shares with his wife.
Dr Kelly would not comment on the costs order, which is due within months, other than to say: ''I can assure you and anyone else there is no risk of this having any bearing on my ability to occupy the seat.''
Dr Kelly said his legal counsel believed he had a strong defence to the substantive defamation action against him, which is yet to be heard.