No. 21 Qualifications of senators and candidates for senate elections (PDF 81KB)
Senators are chosen by the people of each state and territory voting as one electorate at periodic elections. The term of a senator representing a state is 6 years, while territory senators' terms coincide with the term of the House of Representatives.
The provisions governing the qualifications of candidates for election and of senators, once elected, are contained in the Constitution and the Commonwealth Electoral Act 1918 (the Act). The purpose of these provisions is to ensure that the people who stand for, and are members of, the national Parliament are beholden to no-one but the electors as a whole and may therefore perform their duties free from undue external influence, including from the executive government, foreign governments and commercial pressures.
Candidates
To stand for either House, a person must be:
- at least 18 years old; and
- an Australian citizen; and
- an elector entitled to vote or a person qualified to become an elector.
A person who is a member of the House of Representatives or a state or territory legislature must resign before being eligible to stand for the Senate (see s.43 of the Constitution and s.164 of the Act). A person may not make multiple nominations (s.165 of the Act).
Section 44 of the Constitution provides further limitations on eligibility. Broadly, a person cannot be chosen as a senator if the person:
- is a citizen or subject of a foreign power; or
- is attainted of treason; or
- has been convicted and is under sentence, or subject to be sentenced, for an offence under Commonwealth or state law punishable by a prison sentence of 12 months or more; or
- is an undischarged bankrupt; or
- holds an office of profit under the Crown; or
- has a pecuniary interest in any agreement with the Commonwealth Public Service (except as a member of an incorporated company of more than 25 people).
Further, a person convicted of certain bribery or undue influence offences is disqualified from being chosen as a senator for 2 years after the conviction (see s.386 of the Act).
Following numerous cases during the 45th Parliament (2016-19) of sitting senators and members of the House of Representatives found to have been ineligible to stand as candidates, the Commonwealth Electoral Act was amended in 2019 to require candidates to complete a checklist relating to eligibility under section 44 of the Constitution as part of the nomination process. The Australian Electoral Commission (AEC) is required to provide the documents relating to all successful candidates to the respective Houses for tabling.
The Senate subsequently established a Register of Senators' Qualifications. The Register includes the material provided by the AEC, and similar statements made by any senators filling casual vacancies.
For details on grounds for disqualification, see chapter 6 of Odgers' Australian Senate Practice.
Disqualification of senators
The place of a senator who becomes subject to any of the grounds for disqualification in s.44 of the Constitution automatically becomes vacant. Disqualification also occurs if a senator becomes bankrupt or insolvent or if the senator takes, or agrees to take, any fee or honorarium for services to the Commonwealth or for services rendered in the Parliament on behalf of any person (see s.45 of the Constitution). A monetary penalty may apply if a person continues to sit as a senator while disqualified (see s.46 of the Constitution).
Determination of disqualifications
There are two methods of challenging the qualification of a senator. Under each method, challenges are determined by the High Court sitting as the Court of Disputed Returns (CDR).
The first method is under sections 353 to 357 of the Act, which provide that the Australian Electoral Commission, or any candidate or person qualified to vote, may petition the Court, within 40 days after the return of the writ (or, in the case of a casual vacancy, the notification of the choice or appointment) to examine the validity of the election, including the qualifications of candidates.
Possible outcomes include declarations that:
- a person returned as elected was not duly elected;
- a candidate not previously returned as elected is now duly elected; or
- the election is void.
Secondly, the Senate may by resolution refer a question relating to the qualifications of a senator to the Court, under section 376 of the Act.
The order of the Senate establishing the Register of Senators' Qualifications seeks to constrain the circumstances in which referrals to the CDR may be proposed in the Senate. A motion to refer a matter to the CDR may only be moved if the possible disqualification arises from facts not disclosed on the qualification checklist required of candidates for election, and then only after the Senators' Interests Committee has considered and reported on the matter.
Loss of place for non-attendance
The disqualification provisions in the Constitution and the Act are intended to safeguard members of Parliament against undue influence. A person who succumbs to undue influence may be ruled ineligible to stand or may lose his or her place. Senators can also lose their places if they fail to attend the Senate for two consecutive months without permission (leave of absence). Leave of absence motions are routinely moved in the Senate.
Need assistance?
For advice on any of the matters covered by this guide, senators or their staff should contact the Clerk of the Senate on extension 3350 or clerk.sen@aph.gov.au.
Last reviewed: June 2025