Forensic tests on blood and fibres

Blood smears inside Susan Burdett’s south Auckland unit suggest her killer was wearing denim or a fine corduroy, according to tests carried out by a forensic scientist.

The Crown says serial rapist Malcolm Rewa broke into Burdett’s Papatoetoe home in March 1992, raped her and bludgeoned her to death with a baseball bat that the accounts clerk kept for her own protection.

Rewa denies her murder and his defence counsel instead claims Burdett’s son, Dallas McKay, murdered his mother – a claim he strenuously denies.

Sallyann Harbison, forensic scientist and DNA specialist, tested blood and fibres left at the scene. She said patterns left on bloodied bedding next to the body in the master bedroom and on the light switch suggested the marks had been left by blood-stained denim or a fine corduroy.

She also analysed the baseball bat, found lying on the bed, next to the body.

Harbison said there was no visual blood staining on the bat but, with the help of a microscope, she was able to discover four tiny spots of blood.

However, the blood did not give a DNA result.

She said the lack of blood staining on the walls and bedhead meant it was likely Burdett was killed while the duvet was over her head. Harbison also tested swabs from Burdett’s genital area that showed the material was 300 million times more likely to have come from Rewa than another man in the New Zealand population.

Earlier, the jury was shown a police video taken at the scene, days after Burdett was allegedly murdered.

The video, played yesterday at the High Court in Auckland, began with an exterior shot showing a high hedge surrounding a typical brick and tile unit in Pah Rd. Inside the master bedroom, behind drawn curtains, Burdett’s body lay on her bed.

A glory box next to the bed appeared to have been disturbed, there was an indentation in a cardboard tissue box and the doily-like material on top had been moved.

The video also showed the rest of Burdett’s unit.

The house was tidy and ordered – nothing seemed out of place, save for a briefcase on the spare bed and papers strewn on the floor.

Former Detective Senior Sergeant Neil Grimstone, who was the officer in charge of the scene, said it was different to many others he had visited during his career. ‘‘It was very orderly, the whole house was tidy.’’ He told the court 16 fingerprints were found by investigators and all were identified as people who had lawful access to the house.

Grimstone said blood was found on a light switch and a fibre appeared to be stuck to it.

He said the killer could have entered through the open bedroom window and left, either through the same window or the front door. Detectives also failed to find Burdett’s camera and credit card. Grimstone concluded they had been stolen.

Rewa’s DNA was found at the scene and details of 20 of his sexual attacks on women have been read to the court.

The Crown said the 20 other cases shared striking similarities with the Burdett case – the women were home alone, Rewa used violence or threats and the women were often bound and wrapped in bedding.

The trial continues.