The former parliamentary speaker, Peter Slipper, has taken the extraordinary step of making a costs application against the solicitors of the man who brought a sexual harassment lawsuit against him.

Mr Slipper applied to the Federal Court on Wednesday for Harmers Workplace Lawyers and James Ashby, the staffer who accused him of sexual harassment, to pay for the costs of his legal proceedings on an indemnity basis.

The costs awarded by the Federal Court usually amount to between 50 and 70 per cent of the actual proceedings, but costs awarded on an indemnity basis cover the whole cost, and are considered a punitive measure.

It would be rare for the Federal Court to award costs on an indemnity basis, but some lawyers read the judgment handed down by Justice Steve Rares last week as a coded suggestion for Mr Slipper to seek unusual orders.