When serious crash investigator Warren Bunn was called out to a horror smash a year ago this week, he felt his career had gone full circle.

He found the serial drink-driver who had taken the life of Kerikeri mother Katherine Kennedy was the same man involved in an unforgettable run-in he had as a rookie cop 26 years earlier.

Ms Kennedy was driving south on State Highway 10 near Oromahoe last March when Warren Jenkins - who was drinking wine with a mate from Whangarei and driving a car he'd taken from his partner the night before - crossed the centre line.

Her Volkswagen Polo was shunted backwards 25m by the impact, while Jenkins' Nissan Navara ended up on its side astride the highway.

Wine casks were scattered on the road and in the wreckage; a witness said Jenkins and his mate were so drunk they could barely walk. It was not quite 8.30am.

Ms Kennedy was airlifted to Whangarei Hospital but died a few hours later. Jenkins was also flown to hospital, but discharged himself before police could finish interviewing him. He was arrested a week later as he slept in a car on the Auckland waterfront.

When Mr Bunn arrived at the accident scene on March 17 last year, the driver's name immediately rang a bell.

"I said, 'It's not Warren John Jenkins is it?' Sure enough, it was him. You remember certain people over the years," Mr Bunn said.

"We had a meeting in July 1984 when I'd been three years in the job. I stopped him for a minor offence, going through a stop sign on Riverside Drive in Whangarei - but as soon as I stopped him, he came out with a baseball bat."

Mr Bunn managed to avoid the bat - just - and a wrestling match ensued, the pair rolling off the road into a ditch. Jenkins was arrested with the help of passers-by and charged with possession of an offensive weapon, assaulting police, resisting police and drink-driving.

"I remember it because it was out of the blue, after a minor offence on a Sunday afternoon. I felt I'd gone full circle, we'd met again."

Later, Jenkins moved to Auckland where he lived on the fringe of a gang, but over the years his name cropped up in the newspapers.

"Each time I'd think, 'He's in trouble again' - then I heard nothing for years until the crash. It was obvious he didn't do anything with his life from when I stopped him 26 years earlier. In a region with a recidivist drink-drive problem, he's probably one of the worst."

Jenkins' record includes 18 drink-driving convictions and 19 for driving disqualified. He'd been out of jail just 10 days when he killed Ms Kennedy.

The 49-year-old was sentenced in the Auckland District Court last September to four years' jail for drink-driving causing death.

After widespread anger over Jenkins' sentence, the Government promised a review of the outdated penalty for drink-driving causing death (maximum five years' jail) to bring it into line with manslaughter (maximum 10 years).

The Kennedy family also criticised the courts for granting Jenkins bail, even though he fled hospital and had a long record of driving while forbidden.

Ms Kennedy's son, Matthew, is now 6 and living with his uncle's family in Kerikeri.