A forensic scientist has given evidence that a live bullet found beside the body of Robin Bain was not the result of a misfiring of the rifle used to kill him.
Environmental Science and Research scientist Kevan Walsh appeared for the Crown on Friday as the retrial of David Bain continued at the High Court in Christchurch.
David Bain, 37, is accused shooting his father Robin, mother Margaret and siblings Stephen, Laniet and Arawa in their Dunedin home in 1994.
The defence contends Robin Bain killed his wife and children before using the accused's rifle to shoot himself.
The Crown says David Bain shot the family, then attempted to cover his crimes by making it look like Robin Bain killed four family members, then himself.
The defence says that is not the case, using the discovery of a live bullet found beside Robin Bain's body to make its point.
The defence says that live bullet was misfed into the rifle, and that there would be no way that Robin Bain would stay and wait for that rifle to be reloaded before being shot.
But on Friday, Mr Walsh told the court that bullet was not damaged enough and showed examples of other bullets that were genuine misfeeds to prove his point.
Forensic evidence on father's wounds
Two pathologists have told the jury the shot that killed Robin Bain was fired from more than 20cm away, an assessment Mr Walsh said he agreed with.
Mr Walsh said he based his opinion on his own firing tests, and earlier tests completed by another expert.
On Thursday, pathologist Professor James Ferris told the court the pattern of powder scattered on Robin Bain's skin showed the gun would have been fired from a distance of between 30cm and 42cm.
Mr Walsh will be cross-examined next week.