Immunity from summons
It has not been established as a matter of law that any category of persons has any immunity from summons by the Senate or its committees, although theses have been advanced that various officer-holders should be recognised as having such an immunity on grounds of constitutional propriety.[37] Possible and mooted limitations on the Senate’s power to compel witnesses are summarised in ‘The Senate’s power to obtain evidence and parliamentary “conventions”’, paper by the Clerk of the Senate, published by the Finance and Public Administration References Committee, September 2003.[38]
The procedures of the Senate acknowledge that special considerations apply to two categories of office-holders: senators and members and officers of other houses.