UPDATE 2:54 pm: The appeal of Quinton Winders, found guilty of murdering stop-go worker George Taiaroa in 2013, has heard that two jurors approached the judge with concerns about the jury foreman.

Philip Morgan, QC, outlined his case for Winders in the Court of Appeal in Wellington on Tuesday. Winders is appealing his conviction and sentence to at least 17 years in jail in 2016 for the calculated murder of Mr Taiaroa, who was shot dead at Atiamuri, near Tokoroa.

Winders was arrested following a police investigation which took more than two-and-a-half years.

He has always denied killing Mr Taiaroa.

Police and the Crown said the killing was revenge for a minor accident involving Winders' father at the spot a week earlier.

In the Court of Appeal, Mr Morgan's key points in his submission to justices Asher, Clifford and Gilbert included that the propensity for Winders to use firearms was overstated at the trial; that a police interview - where Winders gave crucial background as to his movements around the time Mr Taiaroa was killed - should not have been included at the 2016 trial; that there was conflict between the foreman and two jurors; and that the murder was not as calculated as the judge decided in sentencing.

On the jury issue, Mr Morgan said two jurors approached the judge, saying the foreman was "bossy and unprepared to listen to the views of others".

"If counsel had been aware of this, it may have been necessary to discharge the jury," Mr Morgan said.

"We're talking about a murder trial and for these jurors to raise this, it means there was discord among them that could ultimately affect a verdict."

Mr Morgan said the police interview should not have been admitted at the trial.

"Mr Winders was happy to speak to police but he believed he was there to talk about an incident of reckless driving, not that he was a witness or suspect in a homicide," Mr Morgan said.

"By the time he says 'I need to talk to a lawyer', the damage is done."

Regarding the sentence, Mr Morgan said it could be argued the decision to drive a long distance to shoot Mr Taiaroa was made "on the day", rather than it being a "calculated" decision.