Liberals have no written rules for spill

HOW A FEDERAL LIBERAL LEADERSHIP SPILL WORKS:

* 102 members of parliamentary Liberal party to gather for meeting at Parliament House 9am (AEDT) on Tuesday.

* Motion is listed for discussion.

* WA MP Luke Simpkins will move a spill motion. Don Randall will second it.

* PM Tony Abbott determines whether or not there is a debate.

* Mr Abbott determines if it is a secret ballot or a show of hands.

* Ballot or show of hands is held on whether to spill the leadership positions.

* Whip and deputies count votes and tell party room of the result.

* If the spill fails, the result would be reported to the media and meeting proceeds with other business.

* If the spill succeeds, the positions of leader and deputy are declared vacant.

* Likely to be an immediate call for nominations and a ballot for leader and deputy.

* Liberals have no written rules, only conventions.