The end of a session of parliament is caused by Governor’s proclamation that the Houses have been prorogued. All business before the Houses cease on prorogation.  Consequently, prorogation was used by the government to wipe all business before the Parliament in order to start afresh in a new session.  These days, prorogation is rare during the four year term of a Parliament and only occurs prior to an election.  As the Legislative Council is a continuing House, it is also prorogued until after the election, so that it can’t continue to operate when the Legislative Assembly has expired.  The term ‘prorogation’ has its origins in Latin and means to discontinue temporarily.