The trial in front of Justice Simon France and a jury of five women and seven men has been adjourned for the day, and will continue on Monday.
Mark Lundy, 56, has been accused of committing the vicious assaults in their Palmerston North home in the early hours of August 30, 2000.
Mr Sutherland told the court yesterday the assailant could have stood on Mrs Lundy's bed while bringing the weapon down on her arms and head.
Orange and blue fragments of paint were found on the victims' bodies and embedded into the bones of their skulls, Mr Sutherland said.
The paint was a visual match to paint on the tools in Lundy's shed.
There were no fragments of paint found on Lundy's clothes or in his vehicle, he said.
Mr Sutherland agreed with defence lawyer David Hislop that the attacker's exposed clothing could not have avoided the blood that was being cast off the weapon.
Mr Hislop spent some time yesterday asking Mr Sutherland about contamination at the scene, including when Mrs Lundy was transferred into a body bag and taken out of the house through the conservatory window.
Mr Sutherland said great care had been taken and he was constantly monitoring his and his colleagues' protective clothing to ensure it stayed clean.
He also told the court that particles of blood that could have come from Amber Lundy were found on her father's polo shirt.
Two other marks that also tested positive for blood were also found on the shirt, he said.
The blood particles could have come to be on the top through contamination, Mr Hislop suggested.
Mr Sutherland rejected that. "There was a physical separation of items from the crime scene and the items from Mark Lundy.
"The trial in front of Justice Simon France and a jury of five women and seven men continues.