The traitorous Afghani soldier who gunned down three Australian army personnel in a 'green-on-blue' attack at a patrol base in 2012 is unrepentant, 'remarkably cheerful' and hopes to be released despite being sentenced to death. That's according to a new Four Corners documentary which has revisited the tragic events of the evening of August 29, 2012. That night, Afghan National Army (ANA) soldier Sergeant Hekmatullah, 19, killed Private Robert  Poate, Sapper James  Martin and Lance Corporal Stjepan 'Rick' Milosevic with his M-16 rifle as they relaxed at Patrol Base Wahab, in the Baluchi Valley region of Oruzgan Province. Two other soldiers were wounded.
@highlight
Sergeant Hekmatullah gunned down three Australian soldiers in August 2012
@highlight
He had been serving in the Afghan National Army, which was being mentored by an Australian team
@highlight
The rogue soldier killed Private Robert Poate, Sapper James Martin and Lance Corporal 'Rick' Milosevic
The 24-strong Australian team had been tasked with mentoring @placeholder soldiers and ANA personnel had open access to the Australians.