12/05/2017 08:18 EST | Updated 12/05/2017 11:41 EST

Blood found in apartment matched DNA of off-duty cop, murder trial hears

HALIFAX — Catherine Campbell's blood was found inside the Halifax apartment where the off-duty police officer was allegedly murdered, an RCMP forensic DNA specialist told Christopher Garnier's murder trial Tuesday.

Dr. Gregory Litzenberger told the Nova Scotia Supreme Court jury that he tested various swabs of blood found during a search of the McCully Street apartment.

Litzenberger said blood found in several areas of the flat — including on the TV, floor and stereo speaker — matched Campbell's DNA profile.

Litzenberger said he tested a T-shirt found in a dumpster across the street from the apartment, and two blood stains matched Campbell's DNA.

He also said Campbell's fingernail clippings taken during an autopsy revealed Campbell's blood, while another clipping showed both Campbell and Garnier's DNA.

"Most likely, the explanation would be that there was friction, such as scratching," said Litzenberger when asked how another person's DNA would end up on a fingernail.

Garnier has pleaded not guilty to second-degree murder and interfering with a dead body.

The Crown alleges the 30-year-old man punched and strangled the Truro, N.S., constable inside the McCully Street apartment and dumped her body on a steep embankment near Halifax's Macdonald Bridge.

Evidence presented at the trial in Nova Scotia Supreme Court has indicated Campbell was seen kissing and dancing with a man who bar staff identified as Garnier before leaving with him in the early hours of Sept. 11, 2015.

Also Tuesday, a former digital forensics analyst for the RCMP testified that he examined a computer that was seized as part of the investigation.

Blair MacLellan said he checked its browser history and found searches related to Cipralex, an antidepressant.

He said there were queries for Cipralex and alcohol, Cipralex and violence, and Cipralex and memory loss on Sept. 15, 2015 — days after the alleged murder.

MacLellan said he was told to look for references to "Catherine Campbell" on the computer, but found none. The computer had one user with the name Garnier, he said.

On Monday, the jury watched the first roughly 2.5 hours of a 9.5-hour taped police interview with Garnier on Sept. 16, 2015, after his arrest in the death of the 36-year-old woman.

Garnier could be seen sobbing to RCMP Cpl. Jody Allison as he insisted he "never wanted to hurt anybody."

Last week, the defence put forth a hypothetical scenario suggesting Campbell died during a consensual sexual encounter after encouraging Garnier to choke her.

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