High Court Judge Michael Kirby says despite moves to amend discrimination in a number of federal laws, same-sex relationships have been left behind.
Delivering the Rights Australia inaugural John Marsden lecture in Sydney last night, Justice Kirby said denying homosexuals the civil status of marriage was discriminatory.
He said that while many other countries had adopted marriage or civil union laws to protect the civic rights of same-sex couples, Australia lagged behind.
"In Australia, legislation is presently before the Federal Parliament to rectify the discriminatory provisions in a large collection of federal laws," he said in his speech.
"However, relationship measures lag behind."
Justice Kirby said even civil unions seemed a bridge too far.
"The relationships of same-sex couples can only be registered, rather like a dog or busker's licence."
"I hope that fellow citizens of goodwill who think upon this will not be surprised if many homosexual people in loving relationships say politely to this differentiation: 'Thank you, but no thank you'."
Justice Kirby said the debate on recognition for same-sex unions would continue in Australia.
"The direction of history, at least in countries like our own, seems to be in favour of the abiding principle of the equality of citizens of all ages, races, colours, creeds and sexualities," he said.
Mr Marsden was president of the NSW Law Society and the NSW Council of Civil Liberties during his career.
He died in 2006.
Justice Kirby said Mr Marsden was a considerable achiever, although not without flaws.
"He was courageous and fought tenaciously for civic equality in Australia," he said.
"That is why the lecture has been named after him."
Justice Kirby also used the lecture to criticise sodomy laws, which still exist in more than 30 Commonwealth countries including Zimbabwe.
He said he had been invited to speak on that topic at the 2009 Commonwealth Law Conference in Hong Kong.
"If John Marsden were here, he would be urging us all to lift our voices to tackle this relic of colonialism which, like the death penalty, persists in many Commonwealth countries, supposedly bound together by mutual respect for human rights," he said.
"Whereas in some countries the criminal laws have been repealed and reformed, the root cause for the animosity and hostility to homosexual people remains the teachings of religious leaders.
"The pain that John Marsden felt over the teachings of his church are translated in many countries, including sometimes our own, into violence, blackmail, hatred, stigma and discrimination."
Justice Kirby retires from the High Court next March.
Senate to mull gay couple law changes
Debate will begin in the Federal Senate today over proposed changes to remove discrimination against same sex couples.
Indonesia tells bombers families get ready
8 years ago