Update: Michelle Hoffman-Tamm was mutilated in killing

Rotorua woman Michelle Hoffman-Tamm was intentionally mutilated after a sustained and ferocious attack by her female lover, a court has heard.

Gwenda Leigh Sloane, aka Pluss, 44, was sentenced by Justice Patrick Keane in the High Court at Rotorua yesterday to life imprisonment with a minimum non-parole period of 17 years after previously pleading guilty to murdering 51-year-old Ms Hoffman-Tamm.

About 30 friends and family of both women were in court for yesterday's sentencing, many appearing visibly upset. Afterwards, the sentence was called disappointing and "a joke" by Ms Hoffman-Tamm's children.

Rotorua Crown solicitor Fletcher Pilditch told the court that on November 7 last year Ms Hoffman-Tamm received a text from Sloane, a friend of more than 20 years with whom she was having a casual sexual relationship.

She went to Sloane's Holland St home on her bike and after going to get alcohol they began drinking together.

Sometime that evening, she later told police, Sloane became enraged when she thought Ms Hoffman-Tamm had taken $20 from her wallet.

She launched a frenzied attack with at least two knives that left Ms Hoffman-Tamm with 27 stab wounds and six cutting injuries, 20 of those stab wounds inflicted after death. She hit Ms Hoffman-Tamm over the head with a kitchen drawer and a piece of timber. Both ears were severed and one shoved in her mouth.

Ms Hoffman-Tamm's body lay on the kitchen floor all night before being moved outside by Sloane the next day. The following morning Sloane dumped the body in a ditch near Murupara, covering it with household rubbish.

Mr Pilditch said Sloane was twice interviewed by police investigating Ms Hoffman-Tamm's disappearance but denied knowledge of her whereabouts. However when confronted by police about the text message, she led them to Ms Hoffman-Tamm's body on November 23.

Six of Ms Hoffman-Tamm's family had prepared victim impact statements, including her 25-year-old son Rhys Hoffman, who read his in court.

A tearful Mr Hoffman told the court he was struggling to cope with the loss of his mother, with whom he was rebuilding a relationship.

"I have lost all trust in the world and I understand when people say they have lost everything and it's gut-wrenching," he said.

"I never got to make up for all the times I wasn't there for my mum."

He told the court he used to be "willing to take on anything" but now his outlook had changed.

Mr Pilditch said the crime had a high level of brutality, depravity and callousness and Sloane had gone to extreme lengths to conceal her crime, including repainting part of her flat's interior.

Sloane's lawyer, Harry Edward, said his client's "remarkably early" guilty plea - eight days after being charged - had saved Ms Hoffman-Tamm's family the anguish of a trial, as had the fact she led police to the body.

He said his client was remorseful and had written a letter to her victim's family setting this out.

In sentencing, Justice Keane read out the extensive injuries inflicted before and after death before telling Sloane "your intention could only have been to mutilate her".

The judge put the starting point at 20 years' imprisonment and gave Sloane a three-year discount for her early guilty plea.

Outside court Rhys Hoffman said he had been hoping for a longer sentence.

"There's not much we can do other than take it and move on and hope that everyone else is going to do the same.

. . let my mum rest in peace the way she deserves."

His sister, Monique Hoffman-Tamm, called the sentence "a joke".

"Seventeen years - that would have been nothing to mum. She still would have been in her garden with her hammer and nails."

She said she hadn't yet read the letter from Sloane, who she had called 'aunty' all her life.

"Words don't mean anything at all."

Mr Edward said in his view the judge had been measured and compassionate in reaching his sentence.

"The ultimate sentence was probably stiff but not outside range," he said. "She [Sloane] knew it was going to be significant."

Mr Edward said it was "one of those really sad situations", especially as the two families had been so close.

"They have both in different ways lost loved ones."