Party system

Closer Look – Parliament of Australia and US Congress [PDF 1.89Mb, 16 pages]

Political parties exist to represent the interests of different groups and individuals in society; their ultimate goal is to have members elected to represent these interests. Each party has a unique structure and culture reflecting its distinct history and value system. 

Although the political systems in Australia and the US are dominated by two major parties, Australia's Parliament contains a greater representation of minor parties and Independents. The reasons for this are complex, but the enormous cost associated with mounting a political campaign in the US is often cited as a major reason for the under-representation of minor parties and Independents in Congress.

The following table provides an overview of the distinguishing features of both nations' party systems:

The party system
AustraliaUnited States

Major parties

  • The two major parties are the Liberal Party of Australia and the Australian Labor Party (ALP).
  • Other parties include the Nationals, the Australian Greens, the Country Liberal Party and Pauline Hanson's One Nation.

Major parties

  • The two major parties are the Republican Party and the Democratic Party.
  • Although other parties exist, they are rarely elected.
  • A political party may win the presidency without controlling Congress.

Party discipline

  • Party discipline is very strong and party members are expected to vote with their party.
  • The ALP is the only party that has formal party rules to discourage its members voting against the party, or 'crossing the floor'.

Party discipline

  • Party members decide on an individual basis how they will vote.
  • Party discipline is not imposed, yet party unity in voting is strong.


  • Both houses may contain independent members of parliament.


  • Independents have occasionally been elected; however, they often become associated with one of the two major parties.

In both systems:

  • two major parties dominate the legislature
  • Independents constitute minor membership of the legislature
  • the status of Independents is greatly enhanced if they have the 'balance of power' (the ability to affect a majority vote if the numbers are even) in either house.