Governments are formed in the House of Representatives, but the Senate can decide whether their laws pass. Here’s how the Senate works, how senators are elected, and why the crossbench holds so much power.
Australia’s Parliament has two houses: the House of Representatives and the Senate.
The party or coalition with a majority in the House of Representatives forms government. But for a bill to become law, it must pass both houses. That gives the Senate, the upper house, significant power.
Who sits in it
There are 76 senators. Each of the six states has 12 senators, regardless of population, so Tasmania has the same number as New South Wales. The ACT and Northern Territory have two each.
The equal representation of the states was a key part of the deal that created the federation in 1901, designed to protect the interests of smaller states.
State senators serve six-year terms, with half elected at each normal election. Territory senators serve three-year terms.
How they’re elected
Senators are elected using a system called proportional representation. Instead of winning a majority, candidates win seats by reaching a quota, a set share of the votes in their state.
At a normal half-Senate election, each state elects six senators, so a candidate needs about 14.3% of the vote, after preferences, to win a seat.
On the ballot paper, voters can number at least six parties above the line, or at least 12 candidates below the line.
Because the quota is much lower than a majority, smaller parties and independents can win seats in the Senate far more easily than in the House of Representatives.
The crossbench
Senators who aren’t from the government or the opposition are known as the crossbench. They include the Greens, minor parties and independents.
Governments rarely have a majority in the Senate. When they don’t, they must negotiate with the opposition or the crossbench to pass legislation, often agreeing to amendments in return for support. That can give a handful of crossbench senators enormous influence.
What the Senate does
The Senate debates and votes on bills, and can pass, amend or reject them. It can’t introduce or amend bills that raise taxes or appropriate money, although it can reject them.
Senate committees investigate policy issues and scrutinise legislation. Senate estimates hearings, held several times a year, let senators question public servants and officials about government spending and decisions.
Deadlocks
If the Senate twice rejects a bill passed by the House of Representatives, the Government can ask the Governor-General to dissolve both houses and hold a double dissolution election, where all senators face election. That last happened in 2016.
Critics argue the Senate gives too much power to small parties elected with few votes. Supporters say it acts as a check on government, and makes sure a wider range of views is represented.
