The police officers who responded to a call from Ms Viakaew's landlord on May 12 were greeted by a smell "indescribable and putrid", Ms Reed said.
Viakaew's body was on a double bed in a curtained-off corner of the lounge, covered in blankets, with a dressing gown over the head.
Detective Constable Scott Jones said she was slightly curled up as if she was sleeping and was holding a playing card – the ace of hearts – in her hand, pointed towards her face.
A fan was set up over the bed to try to alleviate the stench, Ms Reed said.
Landlord Ray Goffin said he called police after he went into the house inquiring after her well-being and noticed a "very strong dead smell".
"I'm a ex-butcher and a farmer and I know a dead meat smell. It wasn't right – the state of the place – there was something wrong."
Mr Goffin said he encountered Hieatt in the flat and he said he was Ms Viakaew's boyfriend and that she was not well.
Ms Reed said Hieatt killed Ms Viakaew on April 16 but went about his life as normal – taking trips to Wellington, visiting other prostitutes and going to family gatherings.
An examination of his computer showed he had been on instant chat site MSN with another girlfriend in Thailand during the time his partner lay rotting next to him
. The chat logs showed him saying Ms Viakaew "had gone and she was never coming back".
He later said Ms Viakaew "had made him crazy and he had killed her on Friday".
In other conversations he said he had read jokes for a day to cheer himself up