Forensic scientist details how Steven Wright could not be excluded from DNA samples from evidence

A 2013 case review of items collected at the adult video store where Rene Sweeney was stabbed to death in 1998 was the focus of the Crown's question line on Thursday morning.

43-year-old Steven Wright is standing trial for second-degree murder, accused of stabbing Sweeney in 1998.

Tara Brutzki, with the Centre of Forensic Sciences in Sault Ste. Marie took the stand.

Brutzkitold the court she was approached to conduct the review in May 2013.

Over the years, since23-year-old Sweeney was murdered, Brutzki said DNA technology has made several advancements enabling forensic scientists to make comparisons using smaller samples of DNA, as well as, allowing them to test more complex mixtures of DNA.

Brutzki told the jury she was askedto re-examineitems submitted by Sudbury police from when Sweeney was murdered. The items included a blood-soaked cotton gardening glove, Sweeney's nail clippings and the teal jacket found in a bush area near the intersection of Paris Street and Walford Road.

Brutzki said that the review generated four distinct DNA profiles. She said Profile 1was a match for Rene Sweeney and that the other profiles generated, were from three different men.

Brutzki said she used a "discarded sample" from Robert Steven Wright's mother Wendy. A discarded DNA sample, she emphasized, isn't an item that has been taken from the scene but rather an item that has been thrown away by people of interest to the case, for example cigarette butts. She added that CFS did not collect the sample but received it from police.

Wendy Wright's DNA profile was taken from that sample and compared to the three male profiles detected from the items of evidence, to determine whether she could be excluded as the biological mother of the men.

Brutzki said Wendy Wright couldn't be excluded as the mother of Profile 2 (which was detected in Sweeney'sright hand nail clippings)and the testing results estimated that she was 18,000 times more likely to be the biological mother of Profile 2 than a random person.

'One in greater than one trillion'

The results also found that she couldn't be excluded as the biological mother of Profile 3, which was found in the blood left on the teal jacket. The results showed that she was 330 times more likely to be the biological mother of Profile 3, than a random woman.

However, Brutzki told the court that Wendy Wright could be excluded as the biological mother of Profile 4.

Brutzkitold the court, a discarded sample from Steven Wright, test results found that he could not be excluded as the source for DNA Profile 2. In fact, the probability that the source was unrelated to Steven Wright is estimated to be one in greater than one trillion.

Using another discarded sample from Chris Wright, Steven Wright's brother, CFS found that he could not be excluded as the source of DNA Profile 3. In fact, she said, the likelihood that the source wasunrelated to ChrisWright was one in greater than onetrillion.

Brutzki said from there, she had to figure out whether Profile 4could be the biological father of the sources of Profile 2 and Profile 3. Using a discarded sample from Robert Wright Sr.,the results found that he couldn't be excluded as the biological father of either Profile 2 or Profile 3, assuming that Wendy Wright was the biological mother. Ultimately, CFS found that Robert Wright Sr.could not be excluded as Profile 4.

A November 2019 report released by CFS, Brutzki said, used blood samples taken from Steven Wright and also determined he could not be excluded as the source of DNA Profile 2. The probability that a random person unrelated to him would coincidentally share that DNA profile is estimated by CFS to be one in one trillion.

On Thursday afternoon, the court heard from Sgt. Jeffrey Myatt, a forensic identification officer who was asked by Sudbury police to review the fingerprints and footwear impressions left behind when Sweeney was murdered.

Myatt told the court that he analyzed the fingerprints left at the video store,to see if they were suitable for comparison with a set of five "exemplar" fingerprints. Myatt said the identities of the people theexemplar prints belonged to were not disclosed to himwhen he analyzed them.

Cash tray fingerprints

After analyzing them, Myatt said it was his opinion that bothfingerprints found on the cash traywere a match withexemplar prints, which belonged to Steven Wright.

However, during opening arguments, the defence did not dispute that Steven Wright was in the video store on Jan. 27, 1998. They said hedidn't kill Sweeney.

During the defence's brief cross-examination of both witnesses, they continued to hint atmistakes made by Sudbury police during the early days of the 1998 investigation.

The defence's questions centred around the protective equipment used by both Brutzki and Myatt when they handle items during analysis, how and if they make note of the equipment they wear such as gloves,and the methods they use to ensure items are not contaminated. Myatt told the court that it is the practice of some forensic investigators to document when they change gloves but "it has never been my practice."

Lacy also noted Myatt's previous experience as a forensic investigator and asked him if he would have considered it important to swab items like the tapin the bathroom at the video store, where it's thought the perpetrator washed up. Myatt said if it had been touched, he would have.