Most Australian parliamentarians are affiliated with a political party. From time to time, however, parliamentarians change their party affiliation or sit as an independent while retaining the seat to which they were elected. In the 46th Parliament three parliamentarians changed party. This was fewer than the 45th Parliament when six parliamentarians changed: four of whom did so more than once (see Tables below).

Parliamentarians have offered a range of reasons for why they have joined another party or sat as an independent. For example, Senator Cory Bernardi and Julia Banks MP justified their defections from the Liberal Party by claiming the party had shifted and no longer aligned with their principles. Craig Kelly MP explained his leaving the Liberal Party to sit as an independent as obeying the will of his constituents to continue speaking fearlessly on access to medical treatments, amid the possible threat of losing preselection. Senator Sam McMahon said it was not losing preselection that led to her defection but internal Country Liberal Party politics. Irreconcilable differences have also been cited, such as Senator Steve Martin defecting from the Jacqui Lambie Network (before being sworn-in) and Senators Fraser Anning and Brian Burston leaving Pauline Hanson’s One Nation party. In addition, there may be occasions when a party itself chooses to expel a member.

Legal remedy?

Opinions will probably differ as to whether leaving a party is a problem that needs to be solved, particularly given its frequency in Australian political history. However, given the potential consequences of defecting (which could include a government losing its majority in the House of Representatives), should there be legislation to control such party jumping? When parliamentarians defect there is often a call for them to resign; currently there is no federal legislation or electoral requirement that specifically addresses defections. A defection or a move to sit as an independent may change the dynamics of a legislature.

Constitutional expert, Anne Twomey, has suggested three main reasons for enacting anti-defection laws: to discourage corruption; to maintain the integrity of the voters intentions; and that a single party-defection can potentially bring down a government. However, as Professor Twomey notes, the Australian Constitution exclusively defines all the grounds declaring a seat in Parliament vacant (disqualification, resignation, two consecutive months absence or death in office) and a constitutional amendment (via referendum) is required to add to them. It is only relatively recent that political parties where institutionalised in the Australian Constitution.

A 2003 Parliamentary Library paper on party jumping in Australia and selected overseas countries noted that ‘there is nothing beyond this expression of outrage that can be done—Australia has no law to control what should happen when a defection occurs’.

Professor of Law, George Williams, has suggested that the honourable course for defectors is to resign and stand as independents at the next election as the senators are chosen to represent a party. While there are no formal sanctions against defections, discouragement comes in many forms including negative reactions by former party colleagues, constituents, and the media. Australian parties have an overwhelmingly negative view of party defectors who retain their seats. Defectors can also face calls to vacate their seat, and threats of legal action.

Recommendation 27 of the Joint Standing Committee on Electoral Matters (JSCEM) report into the 2019 election raised considerations of:

• ‘the viability and ramification of determining a seat to be declared vacant when the sitting MP resigns from or leaves the Party under which they were elected’. However, to date the Parliament has not referred any of these issues to the JSCEM.

Political defections are not unique to Australia and occur in many other national parliaments. Some have attempted to tackle the issue through their constitutional and legislative frameworks, such as New Zealand and other southern hemisphere countries. The overall experience of overseas anti-defection legislation has been mixed.

Table 1: Senators who defected during the 45th and 46th parliaments

Table 2: Members of the House of Representatives who defected during the 45th and 46th parliaments

*appointed to fill a casual vacancy under s15 of the Australian Constitution

Party name abbreviations: AC Australian Conservatives; ALP Australian Labor Party; CLP Country Liberal Party; FF Family First; GRN The Greens; IND Independent; JLN Jackie Lambie Network; KAP