The Parliamentary Joint Committee on Intelligence and Security is appointed under section 28 of the Intelligence Services Act 2001(the IS Act). It has three main types of functions, including:

• providing oversight of Australian intelligence agencies by reviewing their administration and expenditure;
• building bipartisan support for national security legislation by reviewing national security bills introduced to Parliament; and
• ensuring national security legislation remains necessary, proportionate and effective by conducting statutory reviews.

These functions are provided for in section 29 of the IS Act, which details many of the Committee’s specific responsibilities, including:

• reviewing the administration and expenditure of the Australian Security Intelligence Organisation (ASIO), Australian Secret Intelligence Service (ASIS), Australian Geospatial-Intelligence Organisation (AGO), Defence Intelligence Organisation (DIO), Australian Signals Directorate (ASD) and Office of National Intelligence (ONI), including their annual financial statements;
• reviewing any matter in relation to ASIO, ASIS, AGO, DIO, ASD or ONI referred to the Committee by the responsible Minister or by a resolution of either House of the Parliament;
• monitoring, and reviewing the performance by the Australian Federal Police (AFP) of its functions under Part 5.3 of the Criminal Code (terrorism);
• monitoring and reviewing the performance by the AFP of its functions under Division 3A of Part IAA of the Crimes Act 1914 (stop, search and seizure powers), and the basis of the Minister’s declarations of prescribed security zones under section 3UJ of that Act;
•  conducting reviews of a range of specific provisions in various Acts relating to national security; including terrorism, telecommunications, citizenship and migration laws;
• reviewing privacy rules applicable to intelligence agencies.

The IS Act also limits the inquiry powers of the Committee by providing that the functions of the Committee do not include:

• reviewing the intelligence gathering and assessment priorities of ASIO, ASIS, AGO, DIO, ASD or ONI;
• reviewing the sources of information, other operational assistance or operational methods available to ASIO, ASIS, AGO, DIO, ASD or ONI;
• reviewing particular operations that have been, are being or are proposed to be undertaken by ASIO, ASIS, AGO, DIO or ASD;
• reviewing information provided by, or by an agency of a foreign government where that government does not consent to the disclosure of the information;
• reviewing an aspect of the activities of ASIO, ASIS, AGO, DIO ASD or ONI that does not affect Australians;
• reviewing agencies' compliance with their privacy rules;
• conducting inquiries into individual complaints about the activities of ASIO, ASIS, AGO, DIO, ASD or ONI;
• reviewing the content of, or conclusions reached in, assessments or reports made by DIO or ONI, or reviewing the sources of information on which such assessments or reports are based;
• reviewing the coordination and evaluation activities undertaken by ONI;
• reviewing sensitive operational information or operational methods available to the AFP; or
• reviewing particular operations or investigations that have been, are being or are proposed to be undertaken by the AFP.

Section 31 of the IS Act requires the Committee to prepare and table an Annual Report as soon as practicable after each year ending 30 June.

The Committee is also required to conduct statutory reviews under other legislation.

Under section 102.1A of the Criminal Code, the Committee may also review any regulations made for the listing (or re-listing) of a "terrorist organisation", and report the Committee's comments and recommendations to each House of the Parliament before the end of the applicable disallowance period (15 sitting days after the regulation was laid before that House).

Further, the Committee may review and report on the declaration of any terrorist organisation for the purposes of section 35AA of the Australian Citizenship Act 2007.

Under the Independent National Security Legislation Monitor Act 2010, the Committee may refer any matter to the National Security Legislation Monitor (INSLM) that the Committee becomes aware of in the course of performing its functions under s 29(1) of the IS Act, and considers should be referred to the INSLM.

The Committee is otherwise not authorised to initiate its own references, but may resolve to request that the responsible Minister refer a particular matter for it to review and, on occasion, is called upon by an appropriate Minister to conduct reviews of national security policy.