Warning: this story contains graphic content
Jurors at the Michael Rafferty murder trial strained to digest the complexities of DNA analysis on Wednesday, but at the end of the day’s evidence, one statistic was plain: By odds of 28 billion to 1, a minuscule bloodstain on a rear door frame of his car likely came from Victoria (Tori) Stafford, the eight-year-old girl he is accused of raping and beating to death.
Mr. Rafferty, too, left a footprint of sorts in his battered 2003 Honda Civic: Microscopic traces of semen, estimated at 250 billion to 1 to be his.
And so did a third person, almost certainly his co-accused and former girlfriend, Terri-Lynne McClintic.
There is only one chance in 11 trillion that minute specks of blood detected on the passenger seat were not from Ms. McClintic, the trial was told, without any elaboration.
Other forensic findings included two blond scalp hairs on Mr. Rafferty’s peacoat, and a scrap of car upholstery that appeared to have come from the Honda’s missing rear seat.
Two scientists from the Centre of Forensic Sciences in Toronto outlined the highly technical forensic data that underpins the prosecution’s case.
Mr. Rafferty’s coat and the Honda were seized after he and Ms. McClintic were arrested in May, 2009, and charged with Tori’s kidnapping and murder.
Mr. Rafferty, 31, has pleaded not guilty to first-degree murder, sexual assault causing bodily harm and abduction.
The tiny red-brown bloodstain was found on a rubber door moulding and derived from two people, one female, CFS biologist Jennifer McLean told prosecutor Michael Carnegie. It was compared to samples from Tori lifted from a lice comb and a tooth and from the two accused.
Definitive conclusions about DNA are rarely presented at murder trials, because they cannot account for every human on the planet. The usual way of assessing such results is by asking what is the mathematical likelihood the DNA belongs to a stranger selected at random.
In Tori’s case, the odds of the blood on the moulding not belonging to her or a relative are 28 billion to one, Ms. McLean testified.
The piece of grey upholstery material found on the floor of the car appeared to match the fabric of the car’s rear seat, Barbara Doupe, a CFS specialist in hair fibres and textile damage, told the trial.
The upholstery was “indistinguishable” from that of a Honda Civic of the same year, the jury was told.
Ms. Doupe testified that the triangular-shaped strip of material, measuring 3.5 centimetres by 0.5 centimetres, had been sliced from the seat with a blade that left cut marks consistent with a blue utility knife seized from Mr. Rafferty.
The Mastercraft utility knife was examined too, she said, but its disposable blade had been removed.
Ms. McClintic has testified that, after Tori was kidnapped from outside her school in Woodstock, Ont., she was concealed on the back seat of the Honda under the peacoat.
In all, 84 different items were submitted to the CFS experts. “It’s on the larger scale of what we normally see,” Ms. McLean said.
Clad in a dark suit and striped tie, Mr. Rafferty for the most part sat quietly in the prisoner’s box, leaning back, his eyes half closed.
But late in the afternoon, he gave a rare display of emotion.
Briefly in the witness box was 30-year-old Alexis Lane, whom Mr. Rafferty had dated until just a few days before Tori was killed.
The prosecution contends that the Honda’s back seat was jettisoned to get rid of incriminating evidence after Tori’s murder, and Ms. Lane was called to tell the jury that when she last saw Mr. Rafferty, both seats were intact.
As she left the courtroom, Mr. Rafferty watched her in tears, leaning forward and wiping his eyes.