Lawyers for the Speaker Peter Slipper are attempting to short-circuit James Ashby's claim that he was justified in leaking extracts of the Speaker's diary to a journalist and a political rival under the implied freedom of political communication in the constitution.

Mr Slipper's legal team has asked the Federal Court for permission to amend their court documents to remove the assertion that Mr Ashby ''unlawfully'' sent extracts of the diary to the News Ltd journalist, Steve Lewis, and Mr Slipper's political rival, Malcolm Brough.

Mr Slipper's solicitor, Josh Bornstein, from Maurice Blackburn, said the move was designed to quash Mr Ashby's argument that there was a freedom implied in the constitution to publish material concerning members of Parliament and Mr Ashby had a duty to expose any wrongdoing.

Whether such a freedom exists and whether it applies in Mr Ashby's case is scheduled be resolved in a two-day hearing set down for October. As it is a constitutional matter, the state and federal attorneys-general have been invited to intervene in the case.

Mr Bornstein said the removal of the word ''unlawful'' would stop the constitutional issue from arising.