Blood found in the boot of a car could have come from a bleeding body, a forensic scientist has told the Louise Tiffney murder trial.
Louise Tiffney, whose son denies murder
Anthony Larkin also told the High Court in Perth that an attempt had been made to wash the blood out of the boot.
Sean Flynn denies murdering his mother in May 2002 and disposing of her body.
Mr Larkin, 38, said he had done more than 400 crime scene investigations and more than a dozen cases where bodies had been transported in car boots.
Mr Flynn is alleged to have murdered Ms Tiffney, 43, at her flat at 2A Dean Path, Edinburgh, before taking her body in the boot of his car to an unknown location.
He also denies previously evincing malice and ill-will towards his mother, and cleaning the boot of his car to avoid detection and hinder forensic examination.
Mr Larkin worked for private company Forensic Alliance when he tested the Nissan Almera, which was owned by Mr Flynn's girlfriend Yvonne Solo, 43, in September 2003.
Some of the staining was "diluted" and appeared orangey, but was picked up using a chemical known as Luminol.
He said Luminol would still pick up evidence of a litre of blood even if one million litres of water had been used to try and wash it away.
Mr Larkin said a number of droplets of blood were also found on the exterior of the white Almera.
He told the court: "It is my opinion that an attempt had been made to remove an area of visible blood staining from an area of the carpet.
"It was certainly not a droplet of blood. It was too large for that. The stain has been expanded when an attempt has been made to remove it."
"It is what I might expect to see from a bleeding person or object being lifted up and put into the boot of the car.
"One of them is a good long run of blood. That's the result of sufficient blood deposited in an area for it to start running down the wall of the car.
"It could be blood which was just dripping off a bloody object or a bleeding person."
The trial, before Lord McEwan, continues.