The Morrison government has faced one of the biggest parliamentary revolts in decades. Five Liberal MPs crossed the floor to pass Labor amendments to the government’s religious discrimination bill in the early hours of Thursday.
The last time any Australian government faced a revolt of this magnitude was when six Coalition senators crossed the floor in November 1982 to support a Labor bill to curtail the power of the Senate to bring down governments by blocking or threatening to block supply.
Crossing the floor is rare, and only seems to be getting rarer, with a minority of federal politicians having ever crossed the floor and just a single politician involved in more than half of all floor crossing divisions between 1950 and 2019, according to data compiled by the parliamentary library.
Large defections have scuttled significant legislation before. In 2006, then prime minister John Howard was forced to drop a bill that aimed to send asylum seekers who arrived by boat to Nauru for processing. Despite three lower house MPs crossing the floor against the bill, with one abstaining, the bill made it to the Senate. But Howard was unable to secure a majority in the Senate despite the government having a slim majority of 39 (out of 76) Senate seats.
At the time, Liberal senator Judith Troeth had vowed to cross the floor against the legislation, and Nationals senator Barnaby Joyce said he planned to abstain from the vote. Troeth would also later cross the floor with senator Susan Boyce to vote in favour of Labor’s carbon pollution reduction scheme.
In 1994, six Coalition senators – three Liberals and three Nationals – crossed the floor to vote against legislation introduced by the Labor government, and supported by the Coalition, which would override Tasmania’s anti-gay laws. Four Coalition MPs had also crossed the floor in the lower house against the bill.
The legislation still passed, legalising sex between consenting adults in Australia and eventually leading to Tasmania repealing its anti-gay laws.
The vast majority of floor crossings happened in the middle of last century according to parliamentary library data, with more than 160 floor crossing divisions by Coalition members while Sir Robert Menzies was prime minister. Malcolm Fraser also saw more than 100 floor crossing divisions while prime minister. But in the past few decades the numbers have dropped off.
There were just over 35 floor crossings by Coalition members while John Howard was prime minister between 1996 and 2007. Malcolm Turnbull’s tenure saw 15 but there were just three under Tony Abbott.
The Labor party had just 29 individuals cross the floor between 1950 and 2019, according to the parliamentary library.
Members of the Coalition tend to cross the floor more often when they are in government than when in opposition. The reverse tends to hold for Labor. Although the Labor party has only been in government for six years in the past thirty, and has seen far fewer floor crossings in total.
The Labor party has strict rules against crossing the floor, with members expected to vote with the party or face potential expulsion. The Liberal and National parties do not enforce voting as strictly.
Data from They Vote For You shows that there were no floor crossings in 2019, one in 2020 and 35 in 2021. But these counts include conscience votes, where parties allow members to vote freely.
Only a minority of MPs ever cross the floor against their party. Since the 50s less than 30% of all members of parliament have ever crossed the floor. The percentage is slightly higher for senators than it is for members of the House of Representatives.
