David Bain trial: Expert tells of finding bloody sock prints

Retired police officer Milton Weir at the trial of David Bain (inset). Photos / Pool

A former forensic scientist has described finding bloody sock prints in the home of David Bain using a chemical process under the cover of darkness.

Peter Hentschel was a scientist working for the ESR in June, 1994, when he was assigned to work with police in examining the house where Bain's parents and three siblings were found dead with gunshot wounds.

Bain, 37, is on trial in the High Court in Christchurch, for the murder of his family, but his defence team say it was his father Robin who killed the family before shooting himself with a .22 rifle.

Mr Hentschel explained today how he sprayed luminol in the house, a chemical that creates a blue glow when it reacts with blood. This process was done in darkness so the glow could be viewed.

Using this process, Mr Hentschel said he was able to find five sock prints, two in the bedroom of David's mother, Margaret, two in the hallway outside the room of David's sister Laniet, and a fifth in the hall at the top of stairs leading to the lower level of the house where David's sister Arawa slept.

Only two of the prints were complete - both in the hallway. Mr Hentschel said he was able to measure these prints by placing his thumbs at either end while the distance was measured by then Detective Sergeant Milton Weir.

Other blood staining and smears found around the house were also described by Mr Hentschel.

One smear was in the doorway leading to the bedroom of David's brother, Stephen. This smear came from a bloody object with a loose weave, Mr Hentschel said.

He agreed it could have come from a green woollen jersey the prosecution says David Bain wore when he killed his family and then washed. Bain's lawyers say the jersey belonged to Robin.

Mr Hentschel said he also looked at the .22 rifle that lay next to Robin's body, and could see some blood stains on it, but others were only revealed after using a special light.

"It was quite extensively smeared with blood."

He said he took five samples of blood from the rifle, but DNA testing was not available then for testing very small quantities. He could recall at least four fingerprints on one side of the rifle.

"When I saw the fingerprints on the rifle, the way they were deposited indicated to me a hand which had blood on it had touched the rifle."

Earlier today a key member of the police murder inquiry into David Bain had a slogan written on his Dunedin home referring to hanging Bain.

Milton Weir, a detective sergeant in charge of the Bain house crime scene after the death of Bain's family, was asked today in the High Court in Christchurch about a witness seeing the slogan "Hang David Bain" painted or spray-painted on his home around 2002.

There was also evidence of the witness seeing a "stick-like drawing pertaining to represent David Bain".

Mr Weir told Bain's lawyer, Michael Reed QC, that the words, "Hang Bain" had been spray-painted on an area of plaster by the door on his house that was to be removed.

He said it was only there for a short time, and it was inappropriate. It came after a function celebrating a Court of Appeal decision on the Bain case in the police's favour.

Mr Weir, whose credibility has been examined in various inquiries, said the slogan would have been written in response to a lot of stress on him and his family.

"I accept it was unreasonable to do that. Inappropriate."

Mr Weir was also questioned today about a pair of socks and a personal note delivered to him by a prostitute named Petra while he was working with the police. It came after police learned that David's sister, Laniet, had been working as a prostitute.

Mr Weir said he had visited a brothel where the prostitute worked in a formal capacity, but found the package bizarre. He said he could not remember any personal note.

Mr Weir was also asked by Mr Reed about an A4-sized electronic notebook belonging to Laniet, which a computer expert said he was handed in 1994 to examine.

But Mr Weir said he had no knowledge of this electronic notebook.

"I know nothing about it."

Mr Reed described it as "very curious" that Mr Weir did not know about it.

Mr Reed today put it to Mr Weir that he had planted a glasses lens in bedroom of David's brother Stephen, that has since become important in the case, because police say it came from glasses worn by David when he struggled with Stephen on the morning of the killings.

Mr Weir "categorically" denied it.

"There is no way that I planted the lens in that room."