A young woman says she begged police to stop hurting her as she lay handcuffed on a carpark floor before a constable allegedly pressed a Taser between her eyes.

"What's his f**king name or I'll f***ing Taser you!"

Mary Jane Takerei claims the threat was made by officer Sean Mathew Doak after she was dragged from a car by police in Auckland's SkyCity Casino carpark on September 17, 2017.

The incident resulted in Doak being charged last year with assault with a Taser and of illegally presenting a restricted weapon.

The 25-year-old constable denies the charges and is on trial in the Auckland District Court this week.

The incident in the underground carpark came after a high-speed police pursuit of a white Subaru, in which Takerei was the passenger.

"It was quite scary," Takerei told the court today. "There was a police car behind us ... I asked him to pull over."

The 23-year-old said the Subaru, driven by a young man, was going "really fast".

Yesterday, on day one of the trial, the court heard the pursuit began in Mt Eden, with the fleeing driver potentially reaching speeds of up to 200km/h.

Police called off its chasing ground units before the Eagle helicopter tracked the car to downtown Auckland.

• Auckland cop accused of illegally tasering woman

After the car's tyres were spiked by police, the pursuit ended in the underground carpark of Auckland's casino.

"I was waiting for the police to come and I heard footsteps," Takerei said.

Doak and his partner, rookie Constable Florence Roberts, were the first on the scene, the court has heard.

Takerei claims Doak opened the car door and said: "Where the f*** is he b****?"

"Did you just call me b****?" She recalled replying to the junior officer.

Takerei said she was then pepper sprayed by Doak.

"It burned really badly ... It just burned my whole face."

Multiple police officers have also said Takerei hit Roberts in the face with a spray from a canister - possibly CRC.

However, this was denied today by Takerei.

"I don't remember any can of CRC or any can of spray," she said.

After being dragged away from the car and handcuffed, Takerei said she "couldn't open my eyes, I could just feel there were a lot of people".

"Please stop, please stop, you're hurting me," she recalled yelling at the police officers.

"Knees were on my back, and I just heard footsteps," she said.

Takerei also rejected claims she was struggling.

"If I was struggling it would've been to just make things stop hurting me," she said.

After leaving the suspect vehicle to try locate the driver, Doak returned to the scene with his Taser drawn, CCTV footage of the incident played to the jury shows.

Crown prosecutor Bruce Northwood alleges Doak assaulted Takerei when he held the weapon near her head as he attempted to elicit information from her about the driver.

The CCTV footage shows Takerei's legs flailing as she lies on the ground while Doak kneels near her head.

"My head got ripped up from the ground," Takerei said.

"I knew it was the same person who peppered sprayed me," she said, remembering the voice of the officer.

"I just felt something on my head."

She claimed Doak yelled: "What's his f***ing name or I'll f***ing Taser you."

But Takerei admitted she could not see what was on her head.

Other police officers at the scene - including Roberts - have testified that they didn't hear Doak threatening Takerei with his Taser or see him pressing it against her forehead and between her eyes as she claims.

Doak's counsel Todd Simmonds said his client was trying to question a young woman who was "vigorously resisting arrest on the ground".

"He kneels down and is demanding to know where is the male and where has he gone, who is he?

"Doing what police officers are expected to do," Simmonds told the jury.

He added while the Taser was drawn and in Doak's hands there was "no threat".

Takerei was later arrested for assaulting Roberts after slamming a car door against the officer's leg.

The wanted driver, the court heard, was later found by police coming out of one of the elevators in the casino as he attempted to slip away.

Earlier today, the jury watched a live Taser demonstration from Sergeant Darrin Putt.

Specifically he showed the arc option, which triggers the Taser to produce an electrical current between two prongs.

Doak is also accused of presenting the Taser and firing the arc mode towards Takerei in the back of his police car when tasked with transporting her home.

Takerei was not shocked by the Taser.

While the arc mode is designed to be a "show of force", Putt told the court, if someone got close enough "it'll bite".

A recording from the weapon also shows the arc mode was activated for a brief moment, the court has heard.

"[Doak] let his professionalism slip badly that night," Northwood said yesterday. "[Takerei] was no threat to him, to others or even to herself. [Doak] used his Taser in two clearly unacceptable ways."

Simmonds said his client accepts he fired the arc mode "for about a second".

But the lawyer said there is no evidence to suggest Doak presented the Taser at Takerei in the back of the police car.

"It was a breach of police policy and he accepts that. And he will have to deal with that internally," Simmonds told the jury.

"He will have to answer to his bosses."

Superintendent Karyn Malthus, the Auckland City District commander, earlier told the Herald an internal police employment investigation will also be conducted pending the outcome of the court proceedings.

The Independent Police Conduct Authority is also carrying out its own investigation.

The trial is scheduled to conclude later this week.