No. 14 Committee membership (PDF 80KB)
Most senators are members of committees during their term of office. There are approximately 40 committees on which senators serve. For further information about the committees, see chapter 16 of Odgers' Australian Senate Practice.
How is the composition of committees determined?
The Senate, through its standing and other orders, determines the composition of its committees. The composition of joint committees is determined by resolutions agreed to by both Houses. The composition of most Senate committees reflects the composition of the Senate itself and the distribution of chairs is also guided by this principle.
The mainstay of the Senate committee system is its legislative and general purpose standing committees (the legislation and references committees).
A government senator chairs each of the legislation committees. The allocation of chairs of references committees is determined by agreement between the Opposition, minor parties and independent senators. Standing order 25(9) provides for the matter to be determined by the Senate if agreement cannot be reached.
For select committees the membership formula is contained in the resolution of appointment of the committee.
How are senators appointed to committees?
Senators are appointed to committees by resolution of the Senate, on the nomination of the Leader of the Government in the Senate, the Leader of the Opposition in the Senate, or minor parties or independent senators, in accordance with the membership formula for the particular committee. This process is done by a letter to the President nominating senators to be members of certain committees which is lodged with the Sub-Table Office. In practice, most nominations are handled by the whips.
It is customary, in relation to positions on committees reserved for cross-bench senators, that these senators will consult amongst themselves before a nomination is proposed. A letter to the President proposing such a nomination should indicate whether this consultation has taken place.
The President announces receipt of the nomination to the Senate. These announcements are included on the Dynamic Red on any sitting day in the afternoons, although they may be dealt with at any time when there is no other business before the chair.
After the nominations are announced, the duty minister moves a motion for the appointment of senators to committees. If the Senate agrees to the motion, senators are appointed to committees accordingly.
What happens if nominations outnumber vacancies?
It is unusual for there to be more nominations than there are vacancies because committee membership is generally resolved by agreement between senators. Where agreement cannot be reached, however, the standing orders provide for a ballot to be held so that the Senate itself may determine the issue (see standing order 25(6) and standing order 27).
Resigning from a committee
It takes a resolution of the Senate to discharge a senator from membership of a committee. Appointments and resignations are dealt with in the letters from nominators and a single motion proposes that senators be discharged from, and appointed to, committees.
Are there different types of membership?
For many committees there is only one type of membership: senators are appointed as "full members" of the committee. Occasionally a senator may be appointed for a period of time, for instance between specified dates or for the duration of a particular inquiry.
For legislation committees and references committees, however, the standing orders provide for different types of membership.
As well as the full members of those committees, the Senate may appoint senators as participating members. Participating members may take part in public hearings and private meetings. They have all the rights of members, including the right to receive copies of submissions and other documentation and to contribute to reports, but they are non-voting members (see standing order 25(7)). As such, they do not affect the composition of the committee but they may count for the purpose of determining a quorum. Participating members are also appointed to, and discharged from, committees by resolution of the Senate as described above. Any senator has the right to attend estimates hearings, participate in deliberations and add to the committee's report (see standing order 26(8)). It is not necessary for a senator to become a participating member of a committee for that purpose.
The resolutions of appointment for select committees usually allow for the appointment of participating members. On occasion, resolutions of appointment of joint committees also allow for the appointment of participating members.
A substitute member is appointed by resolution of the Senate to replace an existing member for a specific period of time, for the duration of a particular inquiry or for the consideration of particular issues. Unlike participating members, substitute members have voting rights in respect of those matters for which they are substituting.
Under standing order 25(7), a participating member of a legislation committee or a references committee may be appointed by letter to the Chair to attend a committee meeting as a substitute for a member who is unable to attend. Committee secretariats can assist senators in making these arrangements.
Quorums
A quorum is the minimum number of members required to be present for a meeting to proceed. As in the Senate, a quorum must be formed if a senator draws attention to its absence (see standing order 29(2)). Standing order 29(1) provides that a quorum in each committee or subcommittee is either a majority of the members or two members, where one was appointed on the nomination of the Leader of the Government in the Senate and the other on the nomination of the Leader of the Opposition in the Senate. Participating members may count towards a quorum if a majority of members is not present.
The Senate may agree to different quorum arrangements for particular committees.
Can senators serve on committees before they are sworn in?
New senators may be appointed to committees in advance of their swearing-in and may serve on committees from the first day of their term of office. In practice, the appointment of new senators to committees from the beginning of a term starting on 1 July is often agreed to in advance by the Senate so that committees may continue to operate with full membership through the transition from one Senate to another.
On occasion the Senate will agree in advance to appoint to committees a person that it anticipates will be chosen by the parliament of a state or territory to fill a casual vacancy. Such appointments take effect from the day the senator is chosen.
New senators may participate in estimates hearings as soon as they become a senator.
Conflict of interest
A senator who has a conflict of interest in relation to a committee inquiry may not sit on the committee for that inquiry. See chapter 16 of Odgers' Australian Senate Practice for further details. Senators may wish to seek advice on such matters from the Clerk.
Need more information about committees?
For assistance with any matters covered by this guide contact the Clerk Assistant (Committees) on extension 3371 or ca.committees.sen@aph.gov.au.
For general information, see:
Last reviewed: June 2025