Robin Bain most likely killed himself, expert tells court

David Bain is on trial for the murders of his parents and three siblings. Photo / Pool

Robin Bain could have shot himself with a rifle up to 22cm from his head, the High Court has heard.

United Kingdom firearms expert Philip Boyce told the Bain murder trial today that Robin Bain, 58, was more likely than not to have shot himself, and the suicide could have been carried out with ease in certain positions.

Mr Boyce is giving evidence for the defence of David Bain, 37, who is on trial in the High Court at Christchurch for shooting dead his parents and three siblings in their Dunedin home on June 20, 1994.

David Bain's lawyers say his father, Robin, killed the family and then shot himself. The rifle used in the killings was found next to Robin's body.

Mr Boyce was supplied with a skull cap and steel rod from New Zealand showing the trajectory of the bullet fired through the head of Robin.

Mr Boyce said his opinion, from analysis of the fatal wound that Robin suffered to his temple, was that the rifle was held against Robin's head, or virtually against his head, in a "close contact" wound.

He said Robin could have reached the trigger with ease with the rifle in certain positions.

And his calculations also showed that the rifle could have been held as far away as 18 to 22cm from the head, with Robin still able to reach the trigger.

Questioned by prosecutor Robin Bates, Mr Boyle agreed that a close contact wound did not rule out a homicide. A person could be taken by surprise and shot with the rifle against the head.

The jury asked Mr Boyce if blood would be expected on the rifle silencer if Robin had shot himself with the silencer against his head. Mr Boyce said it would.

Questioned by defence lawyer, Michael Reed QC, Mr Boyce said he was not aware blood was on the silencer that was never sampled.

Mr Boyce said he also came to the view that the body of David Bain's sister, Laniet, must have been moved, as the gunshot to the top of Laniet's head could not have been administered in the position she was found in.

Laniet Bain, 18, was found in her bed, having suffered shots to the cheek, above the ear and the top of the head.

Mr Boyce said that, in his view, the first of three gunshots Laniet suffered was to the top of the head.

Prosecution experts previously stated the first shot Laniet suffered must have been to Laniet's cheek, which she could have survived, and then sat up before being shot in the head.

David Bain has stated he heard his sister gurgling, and the prosecution say Bain could have heard this after firing the first shot into Laniet's cheek.