Toronto police Const. James Forcillo had undergone use-of-force training, including a "stress inoculation" exercise, three months before he shot Sammy Yatim on a streetcar, killing the knife-wielding teenager.

Toronto Deputy Police Chief Michael Federico — considered by the Crown and defence to be an expert in use of force — testified at Forcillo's second-degree murder and attempted murder trial in Ontario Superior Court in Toronto on Thursday.

Federico refused to testify to the particulars of Forcillo's actions on the night of July 26, 2013, when Yatim was killed. The jury has already heard that Forcillo fired nine shots at Yatim, eight of which hit him.

Forcillo, 32, has pleaded not guilty to the charges. 

Federico did, however, speak about the training Forcillo would have received as a front-line officer, something that is expected to be a central consideration in the high-profile trial.

That training included "stress inoculation," through simulated situations where officers have to use their weapons proficiently while experiencing stress, Federico said.

Federico, a 43-year veteran of the police force, also gave an overview of the equipment standard for Toronto police officers in uniform in 2013 — a pistol, an extendable metallic baton and a chemical spray, best known as pepper spray. 

The province specified the calibre and type of rounds for the pistol, he said, which expand on impact. These bullets "cause more injury," but also "stop the threat."

However, Federico said, "we train police officers to use non-forceful techniques to the fullest extent possible; that would be called de-escalation."

Distance between Yatim and Forcillo?

Earlier Thursday, defence lawyer Lawrence Gridin pressed expert witness Eugenio Liscio to use margins of error to estimate the distance between Forcillo and Yatim.

Liscio came up with an "extreme" minimum of 2.66 metres from the tip of Yatim's knife blade to the officer's gun.

That's about a metre less than what he had previously testified was the likely distance using 3D computer modelling.

That means  Yatim could have leapt off a streetcar and stabbed  Forcillo within a second and a half,  Gridin suggested.

Yatim's mother, Sahar Bahadi, sat closest to the jury taking notes throughout the testimony, while Forcillo's wife, Irina, sat behind her husband on the other side of the courtroom.

Federico is expected to continue testifying on Friday, which will be the eighth day of the trial.

With files from Stephanie Matteis and The Canadian Press