Blood on shovel matches Fredette’s
The chance that the blood found on a shovel in Andrew Watson’s house was not from Lise Fredette is 1 in 26 quadrillion.
Camilla Sewhdat testified about the results of blood found on the shovel in Watson’s first-degree murder and criminal harassment trial on Monday.
Watson is accused of killing Fredette, 74, on Nov. 12, 2014, though her body has never been found.
Sewhdat is a forensic scientist at the Centre of Forensic Sciences (CFS) in Toronto. That’s where all the samples, swabs and items believed to be connected to Fredette’s disappearance were sent for testing.
The shovel was found in Watson’s basement three days after Fredette went missing. When city police discovered it, it was submerged in a bucket filled with bleach and water and there was “red froth” on the surface of the liquid.
CFS technologists created a DNA profile for Fredette using saliva from her toothbrush. Fredette’s son and daughter also provided blood samples to help with their mother’s profile. DNA is inherited from parents in equal amounts, court heard.
Watson, 78, also gave a blood sample for a DNA profile.
“Blood is a very rich source of DNA,” Sewhdat said, adding DNA is found in bodily fluids or skin cells.
During testing at CFS, blood and DNA were detected on the shovel on both the spade and the handle.
The blood found on the spade matched Fredette’s DNA profile.
The odds that someone unrelated to Fredette would share her DNA are 1 in 26 quadrillion, Sewhdat said, and the chance of someone matching Watson’s were 1 in 220 trillion.
The DNA found on the handle of the shovel was a mixture of two people’s. The majority of the DNA matched Fredette’s profile, while the remainder matched Watson’s.
A swab of the “red froth” in the bucket wasn’t able to yield a result, because there wasn’t enough DNA in it. The froth sat atop the mixture of bleach and water.
“We know bleach is destructive to DNA ... it will destroy it,” Sewhdat said.
Four tarps, a yellow nylon rope and a pair of boots were also seized from Watson’s basement and sent to CFS.
Two of the tarps showed signs of bloodstains, but didn’t have enough DNA for testing. The remaining tarps showed no signs of blood.
Blood was detected on the rope, matching the profile of Watson.
And blood found on the left boot also matched Watson’s DNA profile. The boot’s soles were caked in mud.
The driver’s side floor of Watson’s Subaru SUV and the sides of the vehicle had mud splattered on them when it was seized by city police and sent to CFS.
Testing revealed traces of blood underneath the Subaru and in other areas of the vehicle.
CFS technologists didn’t test every area where blood was detected but concluded that Fredette’s DNA was found on the exterior of the Subaru and also in the trunk.
Watson’s DNA was also found in the trunk area, on his seatbelt and near the ignition, court heard.
Swabs of stains found in Fredette’s driveway were also sent to CFS. They were taken the day after she was last seen. Her earring, key and glasses were found at the end of her driveway as well.
The two large stains in front and behind her vehicle were blood, matching Fredette’s DNA profile and a smaller stain – also blood – by the drivers’ side door matched Watson’s.
Sewhdat was the Crown’s 22nd witness to testify during the trial.