The ACT’s ability to determine the size of the Legislative Assembly is a step closer after an amendment to the territory’s self-government Act was tabled in federal parliament on Wednesday morning.

But under the new Bill, any changes to the Assembly's make-up would have to be passed by a two-thirds majority of the Assembly, meaning the major parties would have to agree.

The Australian Capital Territory (self-government) Amendment Bill 2013 was tabled by Regional Affairs Minister Simon Crean in the House of Representatives.

The changes to the Bill do not stipulate a new size for the Legislative Assembly, but instead “amends the mechanism by which the size of the Assembly can be changed”, allowing the ACT to alter the number of MLAs without the approval of the Commonwealth.

“This Bill acknowledges the capacity of the Assembly to run its own affairs by granting it increased legislative autonomy, consistent with the success of its self-governance,” the explanatory memorandum said.

The Australian Capital Territory (self-government) Act of 1988 currently requires the Assembly to have 17 members, with any changes passed by a resolution of the Assembly then needing regulation by the Commonwealth. The proposed amendment removes the role of the Commonwealth, but states any change to the number of MLAs would require a two-thirds majority vote in the Assembly.

ACT Chief Minister Katy Gallagher said the amendment marked an important step for the territory, and said she was hopeful the change could be passed before the federal election in September.

“The size of the Legislative Assembly is properly a matter for the Assembly to decide – in consultation with the ACT community and reflects the self government arrangements that have been in place since 1989.

“An increase to the size of the Assembly will still require a two-thirds majority and remains the ACT government’s preferred approach to ensure that there is bipartisan support for any change to the Assembly’s size,” Ms Gallagher said.

A recent review of the size of the Assembly suggested that Canberrans be asked to double the number of local politicians.

The expert reference group appointed to the review by the territory government publishes its issues paper on Friday, and it includes a suggestion of up to 35 Assembly members representing five electorates, each returning seven MLAs. There are also options in the paper to expand the Assembly from its present number of 17 members to 21, 25, 27 or 33.

The reference group is inviting submissions from the public before the next phase of the review.

Canberrans are easily the nation's most under-represented electors, with just 5.6 elected representatives for every 100,000 people. Victoria has 14.4, with the Northern Territory topping the charts with 75.4.

The reference group noted that the most recent calculations on the cost to taxpayers was about $400,000 per MLA per year, and each minister cost more than $1 million.

Submissions can be made to the Elections ACT website. The panel is due to report at the end of March 2013.

with Noel Towell