A jury has found a man guilty of murder after he deliberately crashed into a car killing the driver.

Tony Worrell, 50, killed Katie Powles on June 3, 2008, at Karaka, Auckland.

He was suicidal at the time of the crash, the jury at Auckland High Court had been told.

Mr Worrell was also found guilty today of causing another motorist, Brett Robinson, grievous bodily harm when he collided with him seconds before he ploughed into Mrs Powles.

He was also found guilty on two counts of attempting to cause intentional damage relating to allegations that he did nothing to avoid hitting four other cars on the same stretch of road.

Worrell broke down in tears and loud sobbing as the verdicts were read out.

He has been remanded for sentencing on December 18.

Prosecutor Kieran Raftery said there was something deliberate about Worrell's actions that night.

He told the jury a person could be found guilty of murder even though they did not intend the person to die.

The defence would say he was suffering a hypoglycaemic attack, but the Crown case was Worrell's behaviour that night pointed to him being drunk.

The jury were told he was more than twice the legal limit to be driving.

Mr Raftery said there was no evidence Worrell tried to change course or attempted to avoid the collision with Mr Robinson's Fiat Uno.

"This wasn't someone gradually drifting ... there was some control there."

That was evidence he wasn't "slipping rapidly into a hypoglycaemic state" but had made a deliberate decision to be in the path of the vehicles.

Matthew Goodwin, representing Worrell, said the accused did not intend to hit any of the vehicles.

"He didn't intend to hurt anybody and certainly had no murderous intent."

Mr Goodwin said he accepted Worrell's driving had tragic consequences and everyone wished they could turn the clock back.

Despite medical witnesses saying it was unlikely he was having a hypoglycaemic attack, the Crown could not exclude that beyond reasonable doubt.

He said that if Worrell was suicidal as the Crown claimed, he could have driven into cars long before he collided with Mr Robinson and Mrs Powles.

The lawyer said the fact that Worrell had his seatbelt fastened was inconsistent with the claim he was trying to kill himself.