Xue's sex defence to murder

It was a tie around the neck and the eyes that opened the argument An An Liu was into deviant sex.

It was not murder, but accidental erotic asphyxiation, Nai Yin Xue Wellington defence lawyer Chris Comeskey argued.

It was another Peter Plumley-Walker.

In 1989 the cricket umpire and ex air force man, complete with a handle bar moustache, had gone to dominatrix Renee Chignall for whipping, bondage and erotic asphyxiation.

"The point of the practice is to produce just sufficient lack of oxygen to increase the pleasure and stop short of the pain of dying," pathologist Dr Timothy Koelmeyer put it.

"And that is a dangerous practice."

During Plumpley-Walker's bondage session he lost consciousness. Chignall thought he had died.

With boyfriend Neville Walker they wrapped him in carpet and put him in the boot of the car and drove to Huka Falls.

Akin to what Xue would also experience, along the way they were captured on security cameras.

Plumpley-Walker was tossed into the falls. When his body was found, it was discovered he had drowned; bondage had not killed him.

Chignall and Walker were eventually acquitted of murder.

Controversial Auckland lawyer Chris Harder who acted for Walker this week sat in the public gallery.

The defence line arose out of the odd placement of the tie on An An's dead face.

It was wrapped around her neck and across her eyes and secured with a loosely tied granny knot.

Their other plank was DNA.

The standard tests on the tie and her panties, found beside her body, had been inconclusive.

ESR applied new YSDR testing which searches for the y-chromosome, found only in males.

Although the samples were less than a pinhead, YSDR found evidence of two separate males on the tie, Xue and unknown man. Both were on the panties too, along with a second unknown man. It was all DNA, not sperm.

Comeskey argued that An An was a secretive woman who had been awakened sexually.

She was enrolled on an internet dating site and there was the wolf remark.

"If that doesn't suggest a young woman of 30 embarking of experimentation and variance, what else does?"

On the day of her death she had gone off in Xue's car to meet the unknown men. For this she left her daughter with Xue.

She left behind her hand bag and cell phone.

For the sex theory to work, the jury would have had to accept the deviant sex took place somewhere else.

And when she died with the men, they would have put her body into the boot of the car and driven it back to 26 Keystone Ave, where she lived.

A single unidentified fingerprint on the rear vision mirror was said to support this theory.

The all woman jury bought none of it.

- © Fairfax NZ News