The Crown in the appeal of convicted murderer Mark Lundy has told the court there is no doubt that DNA found on his shirt came from his wife's brain or spine.
"There is no miscarriage of justice," Philip Morgan QC told the court during his submission.
Lundy's lawyers have been arguing that the test used on the spots found on the polo shirt worn on the night of the murders is unreliable.
His defence raised questions about the use of two specific testing methods of the spots, that was presented as evidence during the 2015 trial.
The two testing methods are called mRNA, which tests what species DNA comes from, and IHC testing, which examines if it is brain or spinal cord matter.
But the Crown argues there is no doubt the DNA was brain tissue of Christine Lundy.
"The tissue is unquestionably central nervous system tissue... it's a fact because a group of world leading experts say," Mr Morgan argued.
Lundy's defence lawyers yesterday also said if Lundy had committed the murders then he would have been covered in blood and brain matter, so there would have been more than two small spots.
Earlier today Mark Lundy's lawyers continued to discredit the scientific test that helped send him back to jail.
Arguing the test called mRNA, which helped detect human cells on the polo shirt that Lundy was wearing on the day of the murders, should not have been used to identify tissue in a forensic setting.
Mr Eaton told the court the complexity of the test was simply too hard for a jury to make a decision on.
He described the test as "uninterpretable" and said that "no jury should ever have been asked to consider it".
"The jury was drowned in a sea of science," Mr Eaton told the court.
It's that complexity that has seen the hearing go on for longer than expected. The hearing was originally set down for two days but is likely to do through until Thursday afternoon. The crown is expected to make its case today.
Jonathan Eaton has again touched on the public's perception of Lundy.
Mr Eaton told the court it was unfair that people have already made their mind up about Lundy.
"Everybody in New Zealand has seen that funeral scene," he said. "The elephant in the room is that funeral scene".
The appeal is ongoing.