The post mortem examinations on the Kahui twins left questions unanswered, a forensic pathologist has told a High Court jury.
Dr James Ferris said some tests that were not completed could have helped to pinpoint the time the injuries were sustained.
Chris Kahui is accused of murdering histwin baby sons, Cru and Chris, in June 2006. He denies the charges and says someone else, probably the twins' mother, Macsyna King, inflicted the injuries that led to their deaths.
His trial in the High Court at Auckland is nearing the end of its fifth week.
Dr Ferris said examination of eye tissue could have given a more accurate time of when the injuries occurred.
He also said it was possible the twins would not have reacted immediately they received their head injuries.
His opinion was in sharp contrast to that of Crown witness Dr Patrick Kelly, who earlier told the trial he thought the babies would have begun to show symptoms within minutes of being injured.
Head injuries sometimes took some time to show and could be missed by people who normally noticed only if there was a seizure, Dr Ferris said.
It could not be ruled out that the babies had been attacked earlier in the day, he said.
However, under cross-examination by Crown prosecutor Simon Mount, Dr Ferris admitted pathologists could not always be precise about the timing of injuries.
