Leonard tried to stop his brother leaving and the two got into a fight on the road outside.
When Hira attempted to drive off, Leonard held on to the open driver's side door by the door handle.
Leonard was dragged along before falling in the gutter at the intersection of Hughes Pl and Howell Rd, motionless.
It is the Crown's case that Hira then did a u-turn, purposely drove back towards Leonard and ran over his head.
But the defence says Hira simply turned around to make his way home.
Leonard was taken to Whakatāne Hospital in a critical condition. He died three days later on November 15 from brain injuries.
This morning, Crown lawyer Richard Jenson, during his closing arguments, said Hira had deliberately run over his brother.
"He didn't stop to check where his brother had fallen. He didn't stop to check his brother was alright. He drove away from the scene.
"At the very, very least this is manslaughter but based on the evidence, there is ample evidence to suggest it was much more than that. It was murder."
Jenson said the injuries Leonard suffered included bruising to the brain, blood clots on the brain, brain swelling and cuts on the brain caused by shards of his skull.
"It was the cumulative effect that led ... ultimately to Leonard Tawa's death."
Jenson said while it was possible some of Leonard's injuries had been caused by the fall from the car, "running over must have caused or increased the severity of all or most of the brain injuries".
Jensen said whether Hira intended to kill or intended to seriously injure his brother did not matter.
"In running over his brother there was a risk he would kill him. Of course, he didn't know for sure his brother had non-survivable injuries but he did know what he had done ... He knew for all intents and purposes he could kill him.
"He knew he was causing injuries that might cause death and he went ahead and did so anyway."
But defence lawyer Gene Tomlinson said Hira had not seen Leonard lying on the road.
"What was in his mind? Get him, kill him, or escape, get away? Was his state of mind anger and rage or panic and fear. Who was the aggressor and who was running?"
Tomlinson said what happened was a "terrible accident" but it was one which was Leonard's fault.
"It was his fault for getting drunk, it was his fault for beating his brother, it was his fault for grabbing onto the car and holding on. It was his fault for causing so much fear and panic that all Hira wanted to do is run. That fear was driving Hira to escape."
Tomlinson said Hira performed a u-turn to get home, not to run his brother over and Hira would not have known if he had hit a person or the kerb if Leonard had fallen next to the curb.
"You must be sure he deliberately caused his motor vehicle to collide with the body and you can't be."
He said even a pathologist who had given evidence could not be sure the car hitting Leonard had been the substantial and operative cause of death. All Leonard's injuries could have been from the initial fall, he said.
"This trial is a tragedy. One son is dead. The other's fate is in your hands. The Crown has not proved the u-turn was a substantial and operative cause of death. Leonard Tawa was not murdered. He died because of the fall in circumstances he created," Tomlinson argued.
"If you are sure the running over was the cause of death, I don't think you can be, but if you were, it was not deliberate. It was a desperate act of a man fleeing to avoid a beating.
"Hira Tawa is not a murderer."
At times during the closing arguments, Hira cried in the dock.
In summing up Justice Lang told the jurors to put themselves in Hira's shoes.
"Put yourself in Hira Tawa's place in the circumstances at the time."
The jury retired to consider its verdict at 2.45pm.
