Former Australian soldier Robert Langdon escapes execution in Afghanistan

Robert Langdon (center) in Kabul

A former Australian soldier sentenced to 20 years in a notorious Afghan jail will be lucky to survive the term, his lawyer says.

But lawyer Stephen Kenny is hopeful his client Robert Langdon's punishment for murder will be reduced.

Langdon, 39, has been spared the death penalty after an appeal and a compensation payment and jailed for 20 years for shooting dead a colleague while protecting a supply convoy under attack from the Taliban in 2009.

Mr Kenny says 20 years in Pol-e-Charkhi jail is tantamount to a death penalty but he hopes further appeals may reduce Langdon's sentence.

"I am hopeful is all I can say," Mr Kenny told ABC News 24 on Thursday.

"The prison in Afghanistan is of course not as good as prisons in Australia - so 20 years in Pol-e-Charkhi in Kabul, you'd be very lucky to survive."

Mr Kenny said the death sentence was commuted after an agreement was settled with the victim's family to provide compensation, known as ibra, and for them to provide forgiveness to his client.

Langdon, from South Australia, was employed by US-based Four Horsemen International as a security contractor when he shot the Afghan security guard.

Mr Kenny said Langdon maintains he acted in self-defence and in fear of his life.

"It was a dispute about whether a convoy should remain in a particular area that Mr Langdon believed was quite dangerous, there were some further complicated reasons that I don't wish to comment on at this stage," he said.

The lawyer said Langdon regretted throwing a grenade into a truck afterwards, thus destroying evidence.

"He now regrets that he did not take the body with him but it was, in terms of destruction of trucks, a standard procedure used in insecure places in Afghanistan."

Mr Kenny has not seen Langdon since May when his client appeared worried and had lost a lot of weight.

Prime Minister Julia Gillard welcomed the fact that Langdon will not face the death penalty.

"We as a government, indeed as a nation, we are opposed to the death penalty," Ms Gillard told reporters in Perth.

"We intercede for Australians around the world who may face the death penalty and register our nation's strong opposition to it."

Consular officials visited Langdon in prison as late as December 28, one of 18 visits made by Australian embassy staff in Kabul as they facilitate visits and delivered supplies.

Langdon's family in South Australia declined to comment when contacted by AAP.

Source: AAP, January 6, 2011