The comments of David Ipp, QC, come amid a sensational ICAC inquiry into the Liberal Party's alleged laundering of illicit campaign finance by routing cheques via Canberra, where there is no dedicated corruption-busting agency.

"It is so screamingly obvious that there is a breakdown in trust at the moment and that the only way of maintaining trust or recovering the trust is to demonstrate that there are adequate means of discovering corruption so that the public can be confident that what the government is doing is not tainted by dishonest behaviour," Mr Ipp told ABC-TV's Four Corners.

An investigation by the program has obtained a copy of the former Rudd-Gillard government's "National Anti-Corruption Plan 2013", prepared by senior officers of the Department of Attorney-General.

The plan aimed to establish a new integrity regime for the vast Commonwealth public service, under which civil servants would be required to report any suspected corruption, but it fell dramatically short of the kind of measures Mr Ipp has said is required.

Critically, it envisaged no new oversight of federal politicians.

Australia is co-chair, with Italy, of the G20's Anti-Corruption Working Group whose reports will be considered by senior G20 officials on Monday and Tuesday, but the government has yet to announce any federal mechanism by which corruption might be investigated and exposed.

Mr Ipp said the establishment of a federal anti-graft commission ''is very important''.

''There is no reason to believe that the persons who occupy seats in the Federal Parliament are inherently better than those who occupy seats in the NSW Parliament.

"Corruption is endemic to the human being. That is, when the opportunities are there, when there is no policing, there are some people who will get involved in that."

But Mr Ipp acknowledged the creation of such an agency was unlikely.

"Most politicians … do not like to be subject to a body such as ICAC and you can see that in all the new similar bodies that have been created in South Australia, Victoria and Tasmania. They really do not have the [same] powers of investigation as ICAC and that is because politicians don't want that."

He said these other anti-corruption agencies would never have been able to uncover the Eddie Obeid plot that delivered his family $30 million from a rigged coal allocation tender in 2008.

"ICAC is able to uncover corruption which other bodies with similar names in other parts of Australia cannot uncover.''

Emily Broadbent, a spokeswoman for Justice Minister Michael Keenan, said ''the national anti-corruption plan was never finished by the former government''.

''The government is developing new anti-corruption measures,'' she said, but did not elaborate on what they might constitute.

The only dedicated corruption-fighting agency in Canberra is the Australian Commission for Law Enforcement Integrity. Its jurisdiction is restricted, however, to Customs, the Australian Federal Police and the Australian Crime Commission. It also has purview over AUSTRAC and sections of the Department of Agriculture, but the vast majority of the public service remains without a dedicated corruption watchdog.

The 2013 national anti-corruption plan also included the creation of an anti-corruption committee chaired by the secretary of the Attorney-General's Department, a "fraud and anti-corruption centre" within the federal police and an "integrity education and training group".

But witnesses to corruption would still be reporting their evidence to heads of departments or the Commonwealth Ombudsman - none of whom have the powers of ICAC to gather evidence and expose corruption.

The secretaries of the Commonwealth public service have long argued there is no need for an ICAC-style body in Canberra.

Linton Besser is a reporter for ABC-TV's Four Corners. The full program can be seen on ABC1 at 8.30pm on Monday.