Jury hears how crime scene DNA, fingerprints were linked to Sweeney murder suspect

Jurors at the trial of Robert Steven Wright spent Thursday listening to DNA and fingerprint experts explain how they helped link Wright to the crime scene.

Wright is on trial in Sudbury for the second-degree murder of Renee Sweeney, who was stabbed to death Jan. 27, 1998, while working at an Adults Only Video store on Paris Street.

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Thursday, an expert from the Centre of Forensic Sciences (CFS) in Sault Ste. Marie explained how advances in DNA technology helped lead to Wright as a suspect – and his arrest in December 2018.

Tara Brutzki, a forensic scientist who manages the CFS’s biology section, explained to jurors that DNA is a “genetic blueprint or set of instructions for all living things.”

“It’s what makes a dog a dog, a horse a horse and a human and human,” she said.

DNA analysis can be used to create a genetic profile, Brutzki said, that comes out as a series of peaks on a graph. Modern techniques have evolved to the point that 15 unique points of a DNA profile can be identified, compared to just four in 1998 when the murder took place.

Brutzki said a cold case review of the Sweeney murder began in 2014, using the more advanced techniques.

She said her analysis determined that blood found on the teal jacket and white garden gloves almost certainly belonged to Sweeney – there was only a one in one quintillion chance that it belonged to another random person.

The jacket and gloves were found near the crime scene soon after Sweeney was killed.

Brutzki testified she also examined DNA taken from other areas of the jacket and gloves not stained with blood, including the inside of the pocket of the jacket and from inside the gloves.

Those tests uncovered DNA from three men and analysis showed a strong possibility it came from Wright, his brother and his father.

Police were able to make the comparisons using “discarded DNA.” That refers to the police’s right to seize items discarded by a subject, such as cigarette butts, and analyze them for DNA signatures.

Police obtained discarded DNA from Wright’s mother, brother and father. Tests showed that she was likely the mother of two of the DNA samples, but not the third – the one associated with Wright’s father.

Brutzki also testified that DNA analysis of debris from Sweeney’s fingernails is linked to Wright, with a probability greater than one in one trillion that it belonged to another random person.

That analysis provides “strong support” for the argument Wright is the source of the fingernail DNA, she said.

He also can’t be excluded as the source of two DNA samples found on the underside of Sweeney’s right hand nail clippings, Brutzki said, with the probability of 1 in 8.2 million and 1 in 420 billion that it was a random match.

Defence attorney Bryan Badali asked Brutzki about the limitations of DNA evidence. For example, Badali said it can’t tell you how a DNA sample got on a piece of clothing or any other surface.

'THERE ARE ALWAYS LIMITATIONS'

“I agree,” she replied. “There are always limitations.”

“Or when it was deposited?” Badali asked.

“I agree, yes,” Brutzki said.

She also agreed that the fingernail clipping debris was not examined in 1998 and that proper handling and storage procedures are key to preserving evidence.

Taking the stand in the afternoon Thursday was Sgt. Jeff Myatt, an Ontario Provincial Police (OPP) fingerprint and shoeprint expert.

Under cross-examination by Crown prosecutor Rob Parsons, Myatt said he was asked to examine two fingerprint impressions from the crime scene: a bloody print found on top of the cash tray at the crime scene, and a latent print found under the cash tray.

He received copies of the prints Feb. 13, 2019, and said he concluded that each print was clear enough to be used for analysis.

He was given several “exemplar” prints for comparison. Exemplar prints are clear fingerprints taken from a known person. Parsons asked if he was able to match both prints on the cash tray with any of the exemplar prints.

“Yes,” Myatt said, adding he linked the prints to ‘exemplar 4,’ which belonged to Robert Steven Wright.

Under cross-examination by Crown prosecutor Rob Parsons, fingerprint expert Jeff Myatt said he was asked to examine two fingerprint impressions from the crime scene: a bloody print found on top of the cash tray at the crime scene, and a latent print found under the cash tray. (Supplied)

In his cross examination, defence attorney Michael Lacy asked Myatt to examine a video still from the bathroom at the crime scene. The jury heard earlier that a coffee cup and soap dispenser shown in the still were removed and not tested for DNA or fingerprints.

Lacy asked whether Myatt would want to examine the soap dispenser for prints, especially if he believed the killer had used it to wash up.

Yes, he replied, but said sinks often have a lot of overlapping prints because so many people use them. The same goes for the tap in the wash basin, but Myatt said it would be standard practice to check the water taps for prints.

“Oh yes,” he said.

Lacy then asked whether deadbolt locks would be a good source of “potentially valuable” prints.

“Yes,” Myatt said.

The jury heard earlier in the trial that blood was found on the deadbolt on the exit door of the crime scene, but Sudbury police didn’t swab it for DNA or check it for fingerprints.

Finally, Lacy had Myatt agree that wearing gloves would reduce the chance of leaving prints.

'LIKELY BELONGED TO WRIGHT'

At the end of proceedings Thursday, Justice Robbie Gordon read a new agreed statement of facts into the record. It dealt with fingerprint analysis of the two cash tray fingerprints conducted by an expert in Reno, Nevada.

That expert, Alison White, concluded the prints most likely belonged to Wright.

The trial resumes Friday morning. CTV News digital content producer Darren MacDonald and videojournalist Ian Campbell are in the courtroom all day and will have updates Friday on CTVNewsNorthernOntario.ca.