‘Crossing the floor’ refers to a politician voting against their own party in parliament. According to research by the Parliamentary Library, 296 individual Australian parliamentarians crossed the floor between February 1950 and April 2019. The Coalition accounted for 90.2% of the individual MPs who crossed the floor compared to Labor’s 9.8%.
This disparity is due to a Labor Party approach known as ‘caucus solidarity’. This means they aim to present a united front to the parliament and voting public. All decisions are debated in the caucus behind closed doors, then all members are expected to vote in parliament for the position reached by the caucus, regardless of their individual position on the issue