Forensic analysis of the patterns of blood stains in the flat of Mei Fan may explain how she was attacked and the subsequent movements of her killer, a court has heard.
ESR scientists spent four days examining Ms Fan's Miramar flat after her body was discovered in the laundry in a pool of blood and with a kitchen knife sticking in her neck.
The 37-year-old had been stabbed dozens of times and her 60-year-old estranged husband Michael Preston is accused of her murder.
His trial, in the High Court at Wellington, entered its third week today, where ESR forensic scientist Janina Neale explained the analysis of the blood found in the flat, either through visible reckoning, luminol testing or chemical enhancement.
It appeared bloodied glove prints – from their regular pattern rather than fingerprints – were left on the laundry wall where most of the blood was found and the major struggle was believed to have happened.
A projected blood stain on the laundry door indicated a volume of blood had hit it with some pressure, perhaps from when an artery was cut.
Other blood stains, from their shape and pattern could be attributed to either blood falling from a height or level with where they landed – just a few centimetres up the wall.
It indicated Ms Fan suffered several blows on or near the floor, Ms Neale said.
The killer, possibly wearing gloves, then walked to the kitchen where diluted blood was found on the blinds above the sink.
They then walked upstairs to the master bedroom where several items were touched with bloodied hands.
The Crown says Preston used latex gloves to cover his hands during the attack and that traces of Ms Fan's blood were later found in his car next to a glove print.
Although partial bloodied shoe prints were discovered, there was not enough evidence to say how big the shoes were, Ms Neale said.
The trial is continuing.