"The sentences imposed were starkly out of the bounds of what was necessary and appropriate," the judgement said.
"Mr Rappel, as well as other offenders serving lengthy sentences for crimes of violence, cannot be allowed to think that more of the same can be carried out with impunity, or even with reduced consequences." Rappel and several others were charged with an attack inside Canberra's jail in 2017, when the two brothers were badly hurt and taken to hospital.
One of the men had 36 individual injuries with cuts and bruises to his face, chest, torso and knee, and a fractured eye socket and broken ribs.Two days into a trial over the matter Rappel pleaded guilty, and charges were dropped against most of the others. But when he was given only six months more in jail, prosecutors took the case to the Court of Appeal saying it was manifestly inadequate.