A retired OPP officer, described by the judge at the Laura Babcock murder as "undoubtedly the most substantial witness of the trial," began testifying on Tuesday afternoon in Ontario Superior Court in Toronto.

"This is a big, long, complex body of evidence," Justice Michael Code warned the jury. "He'll be on the stand for a couple of days."

Jim Falconer, a former detective, will be testifying about all the electronic data that was seized from devices connected to accused killers Dellen Millard, 32, of Toronto, and Mark Smich, 30, of Oakville, Ont.

Both men have pleaded not guilty of first-degree murder in the death of the 23-year-old Babcock, who lived in Toronto. The Crown alleges she was killed in early July 2012, and her body burned in an animal incinerator.

Millard is acting as his own lawyer, while Smich is represented by a team of two lawyers.

From the witness box, Falconer described for the jury some of the things that were discovered on the electronic devices found in the homes of the two accused, including a Steam online gaming account associated with Millard, Word documents associated with aviation company MillardAir, as well as resumés for Millard's then-girlfriend Christina Noudga, and Smich's then-girlfriend Marlena Meneses. 

A Facebook user account belonging to Millard's friend Andrew Michalski was also found, Falconer testified.

Dellen Millard Mark Smich

Dellen Millard, left, and Mark Smich, right, are on trial for first-degree murder in the death of Laura Babcock. (Facebook, Instagram)

Terse answers in cross-examination

Earlier in the day, photos of Millard's expansive Etobicoke, Ont., home were shown in court.

Det. Const. Andrew Ottay of Hamilton police started the day in the witness box, showing pictures he took at Millard's house at 5 Maple Gate Court.

Falconer sketch Babcock trial

Retired OPP Det. Sgt. Jim Falconer (left) appeared in court Tuesday for the trial of two men accused of killing Toronto woman Laura Babcock. Dellen Millard (centre), is representing himself at the trial. Crown lawyer Ken Lockhardt (right) will continue his examination of Falconer Wednesday. (Pam Davies/CBC )

Ottay told the jury Tuesday morning that he was one of several police officers executing a search warrant at Millard's home on May 11, 2013.

He took dozens of photos, giving the jury a glimpse inside Millard's red brick home.

The jury saw Millard's rocky back yard, and a large, empty pool. They saw a wood panelled room with a bookcase tall enough to need a ladder, and fireplaces.

Dellen Millard basement

This photo of the basement of Dellen Millard's home was entered as evidence at the Laura Babcock murder trial Tuesday. (Court exhibit)

They also saw a crowded, messy room piled high with boxes, and what appeared to be an empty aquarium on a kitchen table.

Ottay said it was a large home, with "at least 10 bedrooms."

"There's a very large interior of the house," he said. "Outside, it might look like a small bungalow, but inside there is a multitude of bedrooms and living areas."

Dellen Millard

Co-accused Dellen Millard, right, who is acting as his own lawyer, entered this photo as an exhibit to illustrate his relationship with friend Andrew Michalski. (Court exhibit)

When cross-examined by Millard, Ottay was terse, and gave short answers whenever possible. For large chunks of his cross-examination, he would not look at the accused killer.

Millard repeatedly asked why the officer would not use a cellphone camera when photographing a scene where a search warrant was taking place.

"It's common knowledge … it's not professional to be using phone cameras for a case," Ottay said.

Millard bought new mattress

Court also heard about mattresses Millard had purchased from Sleep Country — one of which was bought right around the time the Crown alleges that Babcock was killed.

Salesman Kulvinder Bassi testified that Millard bought a mattress from him at a Sleep Country store in Mississauga on July 4, 2012. Records showed that Millard paid $2,475.73 for the king-sized mattress, and asked for a rush delivery.

Bassi said Millard also bought a queen-sized mattress on Oct. 21, 2012, and another mattress back in 2010.

During his cross-examination, Millard asked if he seemed "agitated" when he was in the store on July 4.

"No, you were very polite … you were very nice when you came to the store," Bassi responded.

Dellen Millard kitchen

This photo of Millard's home was one of many entered into evidence at the trial on Tuesday. (Court exhibit)

"I didn't seem like I was under a lot of pressure and I was really worried about something?" Millard then asked.

"I couldn't tell," Bassi responded.

The trial will resume Wednesday at 9:30 a.m.

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