The Court of Appeal in Auckland has reserved its decision on the appeal of double murderer Lipene Sila.
Jane Young and Hannah Rossiter, both aged 16, were killed when a car was driven through a crowd of partygoers in Christchurch in May 2007.
Sila, 24, was sentenced last year to 17 years in prison. He is appealing both the sentence and his conviction.
Defence lawyer Pip Hall says Sila was not the aggressor, but was going to the defence of his brother when he himself was attacked.
He says eye witness accounts given at the trial are at significant odds with each other.
Prosecution says Sila acted from anger
Crown Prosecutor Brent Stanaway told the court no jury would have entertained self defence or provocation as a defence based on the evidence.
Mr Stanaway says Sila acted out of anger and his actions were sustained, dangerous and controlled.
The hearing continues on Monday afternoon.