Rota has also denied assaulting police and threatening to cause grievous bodily harm.
Mr Stack gave evidence yesterday that Rota was verbally abusive, aggressive and made obscene gestures when he got out of a parked ute outside Hikurangi Primary School on November 11, 2015.
Mr Stack told the jury it had been about 11.15am when he saw the ute parked half on the road and half on the footpath outside the school.
He stopped his patrol car and said Rota got out of the ute and began swearing, yelling, and giving him "the finger". Rota told Mr Stack to f**k off, the jury heard.
Mr Stack told Rota to calm down, but Rota continued to behave aggressively, about 30 metres from where school children were playing.
Rota pushed him away twice when he tried to arrest him, Mr Stack said.
Rota got back into the ute and reversed into Mr Stack's left hip and stomach area.
Rota was pepper sprayed after he continued to behave aggressively and resist arrest.
Three police officers arrived and helped arrest Rota.
Rota's lawyer John Moroney put to Mr Stack that a week before Rota's arrest, Mr Stack had stopped Rota riding a motorbike on Valley Rd in Hikurangi and said to him: "Get your fat black a** off the bike. It's too big."
Mr Moroney said the officer also commented: "You're a black piece of s*** n*****".
"I did not say that," Mr Stack replied.
The jury heard that the next day, Mr Stack went to Rota's house to issue two infringement notices.
Mr Stack denied that Rota's partner confronted him over calling Rota a "black c**t' the previous day.
Mr Moroney suggested Mr Stack had corrected Rota's partner, saying he called Rota a "black n****r", not "a black c**t". Mr Stack denied this.
Mr Moroney said Rota's partner told the constable that he was not very professional and Mr Stack replied: "I don't give a f***k." Mr Stack also denied this.
Mr Moroney said, on the morning outside the school, Mr Stack had told Rota: "You're going to jail, you black c**t."
Mr Stack denied abusing Rota or using either the "c" or "n" words.
Mr Moroney asked Mr Stack why he had approached Rota, who was delivering his daughter's lunch to school.
"You were determined to engineer a situation that would justify you arresting Mr Rota."
Mr Stack replied "no" and said, if Rota had not acted in a disorderly manner, "we wouldn't be here" - referring to court.
Mr Moroney said it made no sense for Mr Stack to approach Rota's ute with a siren on and blue/red lights flashing.
The officer said it was a requirement for the lights and siren to be on while conducting a traffic stop.
(The trial continues.)
