KEY POINTS:
Chris and Cru Kahui were assaulted just minutes before their symptoms emerged, a pathologist has told a jury in the High Court at Auckland.
Chris Kahui is defending charges he murdered his twin baby boys, Chris and Cru Kahui, in June 2006.
Crown prosecutor Simon Moore read back evidence given by Kahui's sister, Mona Kahui, that baby Cru had gone purple, was flimsy and his eyes were rolling back in his head.
The Crown alleges Kahui bashed his babies in a fit of rage while alone with them in their nursery. Mona came in, found him and went to cuddle Cru when she noticed he wasn't breathing.
Kahui denies ever harming the boys. His lawyer, Lorraine Smith, alleges someone else, probably their mother Macsyna King, inflicted the injuries.
The Crown case is that the babies were injured mid-evening on June 12. The defence disputes the timing of the assault, arguing it could have happened earlier in the evening.
Dr Jane Zuccolo, a specialist in the pathology of babies, said those symptoms indicated the infant had a serious head injury.
Mr Moore asked her how soon after the injuries were inflicted would the symptoms have appeared.
"An infant or young child who has this sort of brain injury ... the symptoms would start immediately or very shortly after." Asked how long "very shortly" was, she replied it was "minutes".
The babies wouldn't have been able to feed normally or wake at the normal times, she said.
Mr Moore asked Dr Zuccolo about witnesses' testimony the babies had their eyes open after the injuries were alleged to have happened.
Dr Zuccolo said the fact a baby with a head injury had their eyes open didn't prove they weren't injured.
Dr Zuccolo told the court reports from witnesses the babies had fed earlier in the day showed it was "extremely unlikely" they were injured then.
Mr Moore read a transcript of a police interview with Kahui who said the boys fed normally about 5pm on June 12.
"If the accused is talking about the feed between 5pm and 6pm ... how likely is it they could have received their injuries before then?"
Dr Zuccolo: "If they were feeding normally then very unlikely."
Mr Moore asked if it was possible the boys fed normally on the Tuesday morning, after the assault allegedly happened, as Kahui claimed.
She said she didn't think it was and she didn't think Cru would have fed at all.
Australian Dr Terrence Donald will be a witness for the defence and will tell the court he thought the incident where Cru stopped breathing was not the primary event following the assault - contradicting Dr Zuccolo's findings.
Defence counsel Michelle Wilkinson-Smith raised the differences in opinion with Dr Zuccolo in cross-examination, asking if she accepted she and Dr Donald had differing viewpoints. She replied they would have to agree to disagree, but still thought the injuries would have been inflicted shortly before Cru stopped breathing.
THE TRIAL SO FAR
The prosecution says
* Chris Kahui, 23, murdered his twin sons, Chris and Cru, when he snapped under pressure.
* The injuries were inflicted in a narrow time frame, meaning only he could have done it.
* Kahui didn't go with the twins to hospital even though he was told they were critically ill.
* He also didn't call an ambulance when Cru briefly stopped breathing.
The defence says
* The twins' mother, Macsyna King, inflicted the fatal injuries.
* She returned home and hurt them when she discovered Kahui wasn't there.
* Cellphone records show Ms King was in Mangere when she claimed she was in West Auckland.
* Defence lawyers Lorraine Smith and Michelle Wilkinson-Smith will call experts who will dispute Crown evidence of when the babies were injured.
