The level of disdain an alleged murderer had for his partner was so strong that he continued his rouse by letting his daughter text her mother - despite her being trapped, dead in a vehicle in the bottom of a lake, the Crown said.

Crown prosecutor Ross Douch this morning delivered his closing submissions in the High Court at Hamilton murder trial of Cory Jefferies who is alleged to have killed Kim Richmond during the early hours of July 31 2016.

Jefferies does admit causing her death but says it was unintentional.

An attack took place in their Ford Ranger vehicle as they headed home after a function at the rural South Waikato Arohena Hall sometime from 3.38am onwards.

Jefferies cellphone data then showed him travelling to Lake Arapuni - in the Ranger - where both Richmond and the vehicle are dumped.

The car, with Richmond in it, were both eventually found 11 months by later.

Through his lawyer Tom Sutcliffe, Jefferies admits killing his partner but says there was no murderous intent and he is guilty of manslaughter instead.

In his closings, Douch today told the jury of five men and seven women that the fact Jefferies had left Richmond "to rot" in the back of the vehicle for 11 months showed the level of "disdain" he had for her.

"It's contemptuous to leave that woman exposed like that to rot in the utility."

As for the threats, a one-off threat could be forgotten. However, repeated threats to various people showed it was having an effect on his state of mind.

"It shows he is preoccupied with the issue and he would like her dead … the defendant said to Mrs Te Brake that he wanted to f***** kill the b**** and what, by his own admission do? He f****** killed the b****."

Douch also urged the jury to remember the lengths Jefferies went to hide what he'd done for 11 months by lying to the faces of his family including his own children.

"How many times do you think they asked 'Dad, when is Mum coming home?', 'Dad, where has Mum gone?' … every time it comes up this man reflects to carry on this outrageous perception on his children.

"He allows his daughter … on the first day to get on the phone and text a dead person. Her mother. That's what he was driven to by what he'd done.

"Here's a man whose relationship was crumbling around him and he was failing to save it."

MURDER OR MANSLAUGHTER

Douch said the case was about murderous intent and Jefferies' state of mind at the time.

Douch explained that intent stretched across the spectrum from a well thought out execution to an almost instantaneous killing where the offender knows death is likely but carries on with the act anyway.

"What looking at there is that you have a position where the killer reaches a state where the level of animosity or anger to the victim reaches the point where he wants to do them harm and acts upon it but in doing that he realises that level of harm can be fatal and does it anyway."

He also urged the jury to put aside any thoughts that what happened between the pair was an affair.

He explained there was no evidence of an "affair" as affairs were usually consummated with a sexual relationship.

"This relationship on the evidence is not worthy of the description of an affair … this is a dalliance between the pair."

Defence counsel Tom Sutcliffe will deliver his closings after the morning adjournment.

KIM RICHMOND FOUND

Kim Richmond was found in a partial foetal position with a portion of her clothes wrapped tightly around the back of her neck with a plastic bag wrapped around her head on the back seat of her Ford Ranger.

Detective Constable James Walker testified how she was facing backwards.

"Most distinctively her chest and stomach area appeared to be free of clothing."

There appeared to be an empty plastic shopping bag like one from a supermarket over Richmond's head and torso. The detective also saw tufts of hair and skin about 200mm higher up on the seat.

Dr Rexson Tse testified that due to Richmond's body being submerged in water for so long he was unable to identify any obvious external or internal injuries or any fractures or bone breaks.

Her cause of death was "undetermined" and he couldn't find any signs of violence.

The couple had spent the night with about 40 other local residents enjoying a pot luck dinner and drinks while watching the Chiefs and Highlanders semifinal match at the Arohena Hall.

They left the hall about 3.38am and some time on the five to seven minute drive home an argument has begun and an attack has taken place in the truck.

The Crown alleges it occurred about 130m from their driveway of their Mangare Rd home.

THE CELLPHONES

GPS from Jefferies' cellphone tracked the vehicle heading to Lake Arapuni at 3.48am.

The signal is eventually lost as there is no reception at the boat ramp.

However, at 4.17am, his phone has again begun tracking his movements back to the family home, at a slower walking pace, eventually arriving about 6.30am.

After arriving home Richmond's phone also began moving again out on to their farm. Its last signal was sent at 8.14am.

The phone was never recovered.