Blood determined with near certainty to be Victoria Stafford's was found on the door of the car belonging to the man accused of killing her, court heard Wednesday.

A mixture of blood from at least two different people on the rubber moulding of the back passenger side door on Michael Rafferty's car was found to contain DNA matching the eight-year-old girl's profile, court heard.

The profile was compiled using her parents' DNA, one of Tori's teeth and a hair from a lice comb, forensic biologist Jennifer McLean testified.

The probability that the female blood on Rafferty's car door was not Tori's, that a randomly selected person would coincidentally share the same DNA profile, is one in 150 trillion, she said.

Results from such a DNA test can either exclude someone as the source of a sample, or find that they cannot be excluded, with varying probabilities that a randomly selected person has the same DNA profile, McLean testified.

Science was the focus Wednesday at Rafferty's trial, where experts from the Centre of Forensic Sciences testified about testing done on several items seized from Rafferty's home and car following his May 19, 2009, arrest.

Rafferty is alleged to have kidnapped Tori outside her Woodstock, Ont., elementary school on April 8, 2009, with his then-girlfriend Terri-Lynne McClintic, and then driven the Grade 3 student more than 100 kilometres away to a rural area, raped her and killed her.

Rafferty has pleaded not guilty to first-degree murder, sexual assault causing bodily harm and kidnapping. McClintic is already serving a life sentence after pleading guilty to first-degree murder.

McClintic testified last month at Rafferty's trial that after she shoved Tori into the back seat of Rafferty's car, he ordered the girl to stay on the floor and covered her with his black pea coat so she wouldn't be seen. A coat matching McClintic's description was found in the house Rafferty shared with his mother, and testing revealed the presence of two blond hairs.

The hairs, found near the left front pocket at the bottom right on the front of the coat, are expected to be the subject of further testimony Wednesday afternoon.

Barbara Doupe, an expert in hair and fibre testing as well as textile damage assessment, testified about how the hairs were found and about testing she did on a small piece of grey material found on the floor of Rafferty's car, a 2003 Honda Civic.

McClintic has testified that Rafferty sexually assaulted Tori in the rear passenger side of his car. As McClintic and Rafferty were driving home after leaving Tori's body under a pile of rocks in a farmer's field, he told her to use a utility knife he had in his car to cut stained pieces of material out of his back seat.

She did so and threw them out the window as they were driving along Highway 401 that night, she testified. But court has heard that police were unable to find such pieces of cloth and foam when they scoured a 51-kilometre stretch of the highway shoulder in May 2009.

A search of Rafferty's car turned up a small, 3 1/2-centimetre by half-a-centimetre piece of grey cloth and foam. Doupe was asked to determine if the material had been cut and with what type of tool.

She found that the piece of material was either from a 2003 Honda Civic or another source of upholstery with indistinguishable characteristics. The material had been recently cut with a "sharp-edged implement," Doupe found.