For ten years, the father of the accused held the position of tehbazari in a vegetable market. He lost to the deceased in a particular tender. The accused's father went to the market the day of the event to buy a basket of melons. The deceased refused to sell it, claiming that another purchaser already had it marked. There were heated exchanges during which the deceased asserted his dominance and declared that his word was final, calling himself the thakedar of the market. This display of power offended the accused's father, who stormed out in a fury. An hour later, the accused's father came back with his three boys, one of whom was the accused. The accused had a rifle, the accused's father had a knife, and the other two brothers each had a lathi. They issued a challenge to determine whose authority controlled the marketplace. The accused shot the deceased dead at close range after taking him by surprise. The defence argued that there was an unforeseen argument between the deceased and the accused's father that took the form of grappling at the time the accused walked to the market with his father and brothers. The accused's father was lathed by the deceased's servants, and it was this beating that drove the accused to defend his father with a rifle. What is the criminal liability of the accused(s), i.e. the father, son of father, the two brothers and the deceased servants?