The Federal Government intends to proceed with its push for Carbon Pollution Reduction Scheme (CPRS) legislation. The CPRS bills as amended after negotiation with the Opposition (see further details), are likely to be introduced in the House of Representatives when Parliament reconvenes on 2 February 2010.

While the Federal Government currently has the option to exercise a double dissolution trigger, it has yet to do so. This is perhaps due to the fact that the amended CPRS is now part of Federal Government policy, and has not yet been presented to the House of Representatives.

If the House approves the amended CPRS in February, the bills will again be presented to the Senate. If the Senate passes the bills, with or without acceptable amendments, then the CPRS legislation will become law.

If the Senate fails to pass, rejects outright, or makes unacceptable amendments, the bills will fail for a third time. This may be sufficient motivation for the Federal Government to use the trigger and seek a double dissolution. However, the likelihood of this occurring is far from certain.

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The CPRS legislation (CPRS No 1) was first introduced to the House of Representatives in May 2009 (the first 10 bills on 14 May, and the 11th on 28 May). The bills were passed, with a number of Federal Government moved amendments (CPRS No 2), on 4 June 2009. The bills were sent to the Senate on 15 June 2009, and rejected outright on 13 August 2009.


The CPRS No 2 was reintroduced to the House of Representatives on 22 October 2009, and passed on 16 November 2009 (13 November being the earliest the bills could again be passed under the 3 month Constitutional waiting period). The CPRS No 2 was sent to the Senate on 17 November 2009.

On 24 November 2009, after significant negotiation, the Federal Government publicly released a series of proposed amendments to CPRS No 2 (CPRS No 3). These amendments were expected to be passed by the Senate. However a leadership spill, largely due to dissent over the CPRS, resulted in Tony Abbott assuming leadership of the Opposition on the day of the Senate vote. Abbott announced that the Opposition in the Senate would seek to have consideration on the CPRS No 2 deferred until the Senate reconvened in 2010, or otherwise reject them outright.

On 1 December 2009, the CPRS No 2 was rejected outright by the Senate. This gave the Federal Government the trigger to call for a double dissolution.

Had the CPRS No 3 been accepted and passed by the Senate, as expected, the House of Representatives could have assented to the amendments and the bills passed into law.


As it stands, the Federal Government has indicated that it intends to present the CPRS No 3 to the House of Representatives when Parliament reconvenes for the first time in 2010 – the likely date will be 2 February (the first sitting day).

As with the other versions, the CPRS No 3 is likely to easily pass in the House of Representatives. What is not clear is what will happen after the bills are introduced again into the Senate. If they are passed, or passed with acceptable amendments, the CPRS will pass into law. However, if they fail to pass, are rejected outright, or passed with unacceptable amendments, a number of scenarios are presented:

  • the Federal Government may seek to renegotiate the CPRS with the new leader of the Opposition, and begin the approval process again, or
  • the Federal Government may let CPRS policy become an election issue, and run the full term of Parliament, or
  • the Prime Minister can act on the dissolution trigger and advise the Governor-General to dissolve Parliament, have a full contested election for both Houses, and seek to pass the CPRS either through numerical superiority in each House, or through a joint sitting

The likelihood of each scenario is dependant on a large number of factors, both political and legal.

Summary of the double dissolution process under section 57 of the Constitution

If the bills are not passed by the Senate, the Federal Government may then advise the Governor-General to dissolve both Houses of Parliament.

If this occurs, both Houses (and notably the full Senate) will be subject to contested elections contemporaneously. Depending on the composition of the Houses as returned a number of outcomes are presented:

  • If the Federal Government is returned and enjoys a majority in both Houses, a joint sitting is not required, and it can be assumed that the CPRS (whichever version the Federal Government prefers) will be passed in both Houses.
  • If the Federal Government does not enjoy a majority in the Senate, the bills will have to be introduced for another round. If the bills (as passed by the House of Representatives) again fail to pass the Senate, are rejected, or are passed with unacceptable amendments, the Prime Minister can advise the Governor-General to convene a joint sitting of the two Houses.
  • At a joint sitting, the Houses will consider the bills as passed by the House of Representatives. The bills must be passed by an absolute majority – that is, more than 50% in favour. As the House of Representatives is approximately double the size of the Senate, it is probable, but not certain, that a joint sitting would result in the bills passing.

Naturally, these outcomes are very dependant on the composition of the Houses as elected. In particular, it has been noted that on current polling statistics, the Greens are likely to be returned holding the balance of power in the Senate. Given the Green party’s criticism of the CPRS No 3, it may be that the Senate would not pass the bills, and a joint sitting would be required.

If a joint sitting were called the legislation considered by the Houses must be whichever version was last passed by the House of Representatives though not by the Senate.


Both Houses of Parliament reconvene on 2 February 2009. If CPRS No 3 is presented to the House of Representatives on that day, given past time frames for a vote, it may be passed by, or around, 9 February (CPRS No 2 passed the first time 4 sitting days after being introduced, and 5 sitting days the second time).

If the bills are sent to the Senate on its next sitting day (22 February), given the past two rounds, a vote may be taken by, or around, 16 March (CPRS No 2 was rejected 10 sitting days after introduction the first time, and 8 sitting days the second time).

The Federal Government cannot seek a double dissolution election any later than six months before the end of parliamentary term. In this case, therefore, 11 August 2010 is the last day a double dissolution election could be called.

The current term of the House of Representatives will expire on 11 February 2011. Therefore, the last possible day for the election to be held, under the normal cycle, is 16 April 2011. Given the history of elections in Australia, however, it is likely that the election will be called earlier.

Other limits to the trigger

A failure by the Senate to pass the Bills will not trigger a double dissolution where the delay is due to the Senate employing its 'customary processes' of debate, consideration and referral to committees.

However, there is an undefined limit on the use of these 'customary processes' at which point the delay will become 'prevarication' and may engage the trigger [See further: Victoria v Commonwealth & Connor [PMA Case] (1975) 134 CR 81].

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