Coorey became a chronic alcoholic and was living as a vagrant when he strangled William Henry Hancox, 65, at his Surry Hills home on January 2 last year.

His counsel, Mr Bruce Miles, told the Supreme Court that Coorey "in his peculiar way did more for the Aboriginal race than anything individually done in the history of the race".

"He did not write a great book. He did not lead the people to the promised land but he did start the Aboriginal Embassy at Canberra. This brought to the attention of the world, and Australia, the plight of the Aboriginal people."

"All the major reforms of modern times came from then," Mr Miles said.

Justice Matthews sentenced Coorey yesterday to nine years' jail with a six-year non-parole period. He had pleaded guilty to a charge of manslaughter

Coorey's downfall had been a tragedy for someone who showed a capacity to be a committed and valuable member of the community, Justice Matthews said.

The victim differed from the accused only in having had a permanent roof over his head, she said. Mr Hancox's house had been in an appalling condition, "long since having fallen into decrepitude", had had the gas and electricity cut off and was lit by lamplight.

Coorey "blundered into it" having mistaken it for a vagrant house, the judge said. But instead of finding shelter for the night, Coorey was confronted by Mr Hancox, who had also consumed large amounts of alcohol and was armed with a bar to repel intruders.

Coorey, 39, was taken by surprise, Justice Matthews said.

When he strangled Mr Hancox he had acted "instinctively, impulsively and without any real regard to the consequences".

Justice Matthews said a shortened non-parole period was justified by Coorey's physical and mental state at the time of the killing and his considerable remorse.