Former Senator Gallagher was found not to have renounced her British citizenship before nominating as a candidate for the 2016 election. In response to the ruling, Ms Susan Lamb, Mr Josh Wilson, Ms Justine Keay and Ms Rebekha Sharkie resigned as well. They also held dual citizenship and did not have their British citizenship renunciation finalised before the deadline to nominate as candidates.
Ms Gallagher’s position will be filled by a countback of the ACT Senate votes in the 2016 election. By-elections will be held in the electorates of Longman, Fremantle, Braddon and Mayo to replace the members of the House of Representatives.
A by-election will also be held in the electorate of Perth following the resignation of Mr Tim Hammond. Mr Hammond resigned to spend more time with his family.