The High Court has ruled that former Family First senator Bob Day was ineligible to be elected to parliament, and that his South Australian Senate seat should be filled by a special recount of ballot papers.
The High Court ruled on Tuesday that Day's election was invalid because his commercial interest in the government-held lease on his electoral office breached the Constitution.
This means there will be a special recount of the South Australian ballot. The seat could fall to the number two on the Family First ticket Lucy Gichuhi, or former Labor senator Anne McEwen, who lost her seat in 2016.
With Day's name excluded the preference flow would go to number two Gichuhi. But if Family First's ticket is deemed invalid, all votes from the party would presumably flow to McEwen.
A single justice will make further directions and orders necessary to finally determine the matter, and how the special recount will proceed.
Day resigned last October after his construction business Home Australia Group went into liquidation.
Given the sitting schedules of the High Court, SA Parliament and Federal Parliament it is unlikely a new senator will be sworn in before the budget in May.