Updated

An Australian judge threw out a sexual harassment lawsuit against the former Parliament speaker Wednesday, dubbing it nothing more than a political attack aimed at ruining the man's career and advancing the interests of the nation's opposition party.

Peter Slipper resigned as House of Representatives speaker in October, weakening the government's tenuous grip on power, after his media adviser James Ashby accused him in the lawsuit of sexually propositioning him.

Prime Minister Julia Gillard's center-left Labor Party government had recruited Slipper from opposition ranks to the speaker's post in a move that effectively gave Labor, which holds a razor-thin majority in Parliament, an additional vote on most legislation. When Slipper resigned, Gillard was forced to rely on independent and minor-party lawmakers to pass her legislative agenda.

Slipper, who is married, denied the sexual harassment allegation and argued the lawsuit had been designed solely to hurt him and destabilize the government.

Federal Court Justice Steven Rares agreed, and found that Ashby and a colleague had used the lawsuit in a bid to boost their careers with the opposition Liberal Party.

"I have reached the firm conclusion that Mr. Ashby's predominant purpose for bringing these proceedings was to pursue a political attack against Mr. Slipper and not to vindicate any legal claim he may have," Rares wrote in his decision.

Rares did not rule on whether Slipper was guilty of sexual harassment. The judge dubbed the lawsuit an abuse of the judicial process, and ordered Ashby to pay Slipper's legal costs.

Slipper said he felt vindicated.

"I have always maintained that Mr. Ashby's application was about manipulating the justice system to inflict damage on my reputation and political career and to advance the interests of the Liberal National Party," Slipper said in a statement.

Ashby said he planned to appeal.

"There's been a determined campaign to try and prevent the substantive allegations being heard and judged in open court and to put me at a maximum cost in pursuing justice," he told reporters outside court.