A North Shore man is on trial for the manslaughter of his partner, whom he denies assaulting.

Almost a year to the day of the death of Lee Hart, 53, who suffered a brain bleed and died, the trial of her partner Kevin Leslie Everett began this morning in the Auckland High Court.

Everett pleaded not guilty to manslaughter last year when it was alleged he assaulted her on or about February 12 2017 causing her death the next day.

Opening the case for the prosecution Erin Woolley said the outside world could be a "long way removed" from what was really happening in a relationship behind closed doors.

Advertisement

But that was "not quite" the case here as the pair were often overheard yelling at each other.

Everett belittled Hart, called her names and put her down in front of people, Woolley said.

"Ultimately he thought she was annoying and a pain."

The day before her death, on February 13, 2017, a witness noticed the victim was shaky and had a puffy face, Woolley said.

There were lumps all over Hart's head, she said.

"She was complaining of having a headache."

The next day the witness came to check in on her and realised she needed to be taken to a hospital immediately. Hart underwent emergency brain surgery.

About 24 witnesses would be called by the Crown, one of which they contend saw Everett hit Hart two days before her death.

Advertisement

Everett said she always fell over "because she drank too much", Woolley said.

"The crown does not need to prove that he intended her to die."

Defence lawyer Peter Syddall said Everett denied assaulting the victim.

"The issue is simple, Mr Everett comes before you today because he can not and does not accept what the Crown has accused him of doing."

Everett had the right to be presumed innocent and the burden was on the Crown to prove otherwise, Syddall said.

"You must be sure," he told the jury.

"You must be sure that each element required to be proven has been met.

"You are the judges, you don't have the luxury of emotion."