A 70-year-old Whangārei driver was duped out of her van by an intoxicated thief who claimed she had a flat tyre and offered to help fix it.

As she went to inspect the wheel, the woman left her keys in the ignition, unwittingly giving Anthony Caldwell, 60, the opportunity to jump into the driver's seat and start the engine.

She banged on the back windscreen for him to stop but he reversed towards her.

The woman got out of the way in time to avoid being injured.

Caldwell, a sixth-time drink driver with four previous convictions for unlawfully taking vehicles, accelerated away. Pursued by police, he only stopped when patrol cars boxed him in.

A breath-test returned a reading of 600 micrograms.

The van was recovered, undamaged, after the September 19 theft.

Caldwell told police he was drinking in the Tikipunga Tavern, in Whangārei, and having had his fill, left carrying a bottle of beer. He approached the woman at the Paramount Plaza Shopping Centre carpark where she had just finished loading her groceries and was about to leave.

He told police he thought the woman was his aunt from Te Awamutu - a comment that dismayed Judge Philip Rzepecky, who remarked on it while sentencing him in Whangārei District Court.

The comment was "really unbelievable", the judge said.

"You shouldn't treat your aunt like that.

"What a crazy thing to say, it sort of belies the whole night," the judge said.

Caldwell pleaded guilty to unlawfully taking a vehicle, drink-driving for a third or subsequent time – his sixth - failing to stop, and aggravated assault for reversing the vehicle towards the woman).

He was also sentenced on a separate admitted charge of disqualified driving about a month later.

Police wanted him jailed as was recommended by a pre-sentence report which assessed Caldwell as being alcohol dependent with a high risk of reoffending and harm to others if he did not stop drinking.

A prosecutor said the sixth-time drink-drive conviction alone justified an 18-20 month prison term - even before the aggravating features were taken into account.

Judge Rzepecky said it was hard to disagree but he accepted defence lawyer Braden Harris' submissions home detention was the least restrictive outcome and appropriate in the circumstances. Caldwell had self-referred for help with his alcohol problem and had prospects of rehabilitation, which home detention would enable him to continue.

There had been a positive restorative justice conference and Caldwell was lucky the complainant had been so "generous and forgiving", which particularly swayed his decision, the judge said.

At the conference, Caldwell told the woman he had since stopped drinking and offered to do household jobs for her. The judge said he hoped Caldwell would honour that offer.

Using the unlawful taking of the vehicle as the lead offence, the judge set a sentence starting point of 15 months, uplifting it by six months for the aggravated assault, and a further two months for drink driving.

Home detention conditions banned him from consuming alcohol and other drugs.

There were no post-detention conditions.

For the main group of charges, Caldwell would be subject to alcohol interlock and zero-alcohol licence provisions.

Dealing with the later disqualified driving charge separately, the judge granted Caldwell a waiver from mandatory disqualification imposing 40 hours of community work in lieu of it. He noted Caldwell had his licence reinstated a week and a half before the main set of offences.

Caldwell was warned he would be jailed for a further offence.

- Sarah Curtis, Open Justice