A forensic scientist was concerned about the possibility that police footwear may have contaminated the murder scene where Christine and Amber Lundy were bludgeoned to death, the Mark Lundy murder trial was told yesterday.
Mrs Lundy, 38, and 7-year-old Amber, were both killed after they were attacked by a tomahawk-like weapon on August 30, 2000.
Mark Lundy, 56, has been accused of carrying out the attacks on his wife and daughter at the family's Palmerston North home.
As the trial concluded its third week yesterday, defence lawyer David Hislop continued his cross-examination of ESR scientist Bjorn Sutherland, and once again mentioned the possibility the crime scene may have been contaminated.
Mr Hislop referred Mr Sutherland to his notes, in which he had talked about a discussion he had with another police officer while examining the crime scene.
In this conversation, Mr Sutherland mentioned he was concerned that police may have transferred some blood while luminol tests were being carried out.
Mr Sutherland told the court that stepping plates, used to avoid contamination, were removed before luminol testing was undertaken.
Mr Sutherland had noted his concern that areas of the home may have been contaminated by the footwear of other police officers at the scene.
He said areas which tested positive for luminol did not have a "verifiable" pattern so police were unable to determine what the patterns were, and where they had come from.
Mr Sutherland also told Mr Hislop that luminol testing was carried out after blood samples were collected for DNA testing, so samples would have already been removed from the crime scene.
The trial before Justice Simon France and a jury continues on Monday.