A jury in the retrial of murder accused David Bain has been told there is no accurate, chronological order of what happened at the scene of the crime after police arrived.
Mr Bain is being retried on charges of murdering five members of his family in Dunedin after an order by the Privy Council in 2007.
The Crown says Mr Bain, 36, murdered his parents Robin and Margaret and siblings Arawa, Laniet and Stephen at the family's home in June 1994.
The defence says Robin Bain killed the family present in the house before shooting himself.
At the High Court in Christchurch on Monday, the jury heard evidence from several former police photographers who took photos of the crime scene, with the defence raising questions over pictures taken.
Former police photographer Trevor Gardener, the first witness to give evidence for the Crown, said under cross-examination that too much time had lapsed since the crimes occurred for him to remember what photographs he took of the scene.
Mr Gardener said he had not switched on the time-coding function on his camera, so there was no way to tell what time and in what sequence each photo was taken.
Defence lawyer Helen Cull, QC, put it to Mr Gardener that items had been moved because they were in different positions in different photographs.
Mr Gardener acknowledged that it was clear from the photos that some items in the crime scene had been moved, but he could not recall why.
Mrs Cull put it to another former police photographer, Kenneth Chilton, that he could not remember which photos he had taken, or who had instructed him to take them.
"Essentially, you can't positively identify from this exhibit which are your photos and which aren't - that's fair, isn't it?," she asked.
Mr Chilton replied: From the exhibit, yes."
The jury was shown photos of a bruised David Bain taken after his family were found dead.
Former police photographer Daniel Batchelor took photos of a bruise on Mr Bain's head and a scratch on his leg.
The Crown argued that these are signs of a struggle that occurred while the murders took place, but Mr Bain denies any involvement.
Bain 'distressed' at images
The court was shown graphic video footage of the crime scene on Monday and Mr Bain appeared distressed at images of his dead family members.
The accused covered his mouth with his hand and looked away as a video of the crime scene panned over the body of his father, Robin Bain.
It was the first sign of emotion from David Bain, who so far has appeared calm and relaxed since the trial began on Friday.
Mr Bain has served 12 years of a life sentence before the Privy Council quashed his convictions.
The Privy Council judgment in 2007 made it clear that the original verdict was not necessarily wrong, but that Mr Bain had not been given a fair trial.
The trial will continue on Tuesday and is expected to take about three months.