Speaking five days after a fracas embroiling the Prime Minister, Julia Gillard, he said: ''I struggle with this hypocrisy, particularly when they seem happy to intervene in the affairs of other countries but become very defensive when criticised for their treatment of the first peoples of this land.''

Mr Dodson was delivering the inaugural Gandhi Oration at the University of NSW.

Mr Dodson defended the expert panel he co-chairs against criticism that it had gone too far in recommending changes to the race powers contained in the constitution to allow positive discrimination for indigenous people. He said there should be no referendum on it if politicians did not agree.

''If there is no cross-party support for the proposition, it will more than likely fail,'' he said.

Earlier in the day, Anne Twomey, the director of the constitutional reform unit at Sydney University's law school, warned that the ''complexity and extensive reach'' of the panel's proposals would probably result in their failure if put to a referendum.

Mr Dodson defended the Aboriginal tent embassy in Canberra, which was the source of the protests on Thursday that led to a security scare involving Ms Gillard and the Opposition Leader, Tony Abbott.

''It would be simplistic … to condemn outright the behaviour of protesters associated with the tent embassy last week, without considering the sense of oppression that some of our people still feel toward our governments on a whole range of matters,'' he said.

''I will always condemn bad manners and unnecessarily aggressive behaviour by whomever. But I will always defend people's rights to assert their political position and try to look to the heart of why people feel so oppressed that they feel violent confrontation is the only recourse to the resolution of their position,'' he said.

Customary laws, which sustained indigenous societies for millenniums, remained subjugated to those of the settler state, while Aborigines remained over-represented in jails and still died on average 10 to 17 years earlier than other Australians, he said.

If there was any parallel with Gandhi's wish to ''get the Empire out of India'', it would be to displace the rule of the public service from Aboriginal people's lives so they could express indigenous values that existed in Australia before the British arrived, he said.

In the continuing political fallout from the fracas on Australia Day, the opposition implied the federal police had acted prematurely by announcing there would be no investigation because there was no evidence of a criminal act concerning a tip-off by Mr Gillard's aide Tony Hodges which led to protesters knowing Mr Abbott's whereabouts.

The shadow attorney-general, George Brandis, wrote to the federal police commissioner, Tony Negus, suggesting he participate in a ''thorough'' investigation.

Senator Brandis said it was impossible to conclude there was no need for an investigation without talking to the key players, including Mr Hodges, and Kim Sattler, the union official he told that Mr Abbott was at a function near the tent embassy.

Senator Brandis said inconsistent statements by Ms Sattler warranted investigation, and the police should ascertain whether Mr Hodges acted alone or with fellow staff members.

Mr Negus said the police would consider Senator Brandis's request.

The disgruntled independent MP Andrew Wilkie said he would support debating a motion of no confidence in the government when Parliament resumed next week.

But Mr Abbott does not plan to introduce such a motion, which would not pass.

The Greens said it was time the opposition moved on from the incident.

with Dan Harrison