Structure of parliament


Generally, the party that wins the most seats at an election will form government. Where a party does not have a majority in its own right (13 seats), it requires the support of members of the crossbench to form government.

Of the nine Assemblies since self-government, only one—the Sixth Assembly—had a government where a single party (the ALP) was able to achieve a majority in its own right. Governments from the other eight Assemblies have required the support of the crossbench to achieve a majority.


Ministers are appointed by the Chief Minister, and together they make up the executive. The Australian Capital Territory (Ministers) Act 2013 specifies that the executive will be made up of no more than nine ministers.

The executive is responsible for administering the laws of the ACT, making administrative decisions, managing the budget and providing services to ACT residents.

The members of the executive usually come from the same political party, however, in 1998 an independent member was appointed to the executive in a Liberal Government. In 2012 and 2016, a member of the ACT Greens was appointed to the ministry in a Labor Government.

The executive determines its policies through decisions made by the cabinet. In the ACT, all ministers are members of the cabinet, which is chaired by the Chief Minister. Cabinet considers all important questions of government policy, administration and legislation.

Ministers’ responsibilities include:


The formation of an official opposition is a feature of parliamentary democracy based on the Westminster system of government, which Australia inherited from Britain.

The largest non-government party elected forms the official opposition.

The opposition’s role is to question what the government does, to scrutinise government policies and administration and to highlight any weaknesses or deficiencies in government decisions or the implementation of government decisions. The opposition will often present its own alternative policies as well.

Shadow ministry

The opposition nominates a number of its MLAs to be responsible for commenting on particular areas of government activity. These opposition members are referred to as shadow ministers.

In the chamber, shadow ministers will often ask questions of the ministers that they ‘shadow’ and will also take the lead in debating issues connected to their areas of shadow portfolio responsibility.

Non-executive members

All members who are not ministers are known as non-executive members. Non-executive members participate in votes, move motions, introduce bills (called private members’ bills), ask questions during question time, raise matters of public importance, and lodge petitions.

Non-executive members also play a critical role as members of the Assembly’s committees.


Members who are not ministers or shadow ministers are referred to as backbenchers. They usually sit behind the ministers and shadow ministers (the government sits to the right of the Speaker, and the opposition to the left).


The Assembly chamber is built in the shape of a horseshoe. Members from minor parties and independent members sit in the curved part of the horseshoe, known as the crossbench.

When the governing party does not hold a majority of seats in the Assembly, crossbench members may hold what is commonly referred to as the ‘balance of power’. Their vote may decide the outcome of an issue that is before the Assembly when the government and opposition hold opposing positions.


The Speaker is the Presiding Officer of the Legislative Assembly who sits at the table at the front of the chamber and is responsible for maintaining order, interpreting and applying the Assembly’s standing orders and generally ensuring the smooth operation of Assembly proceedings.

Although a member performing the role of Speaker will typically be a member of a political party, it is important that they are able to perform the job in an impartial way that is seen to be fair by all members. More information about the role of the Speaker is provided in the fact sheet, Responsibilities of Members of the Legislative Assembly for the ACT.

The other people at the table

There are two other people who sit at the front table in the chamber. Unlike the members, they have not been elected by the people, but they have very important roles.


The Clerk is the most senior permanent official in the Assembly. The Clerk is responsible for the administrative functions of the Office of the Legislative Assembly, provides procedural advice in the chamber, and announces the business before the Assembly.

Deputy Clerk and Serjeant-at-arms

At the Legislative Assembly for the ACT, the Deputy Clerk, who supports and sits alongside the Clerk in the Chamber, also holds the role of Serjeant-at-Arms. As Serjeant-at-Arms, they are responsible for carrying out orders of the Speaker in relation to security, and have ceremonial duties leading the Speaker in and out of the chamber while carrying the mace.

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