TORONTO -- The lawyer for a Toronto police officer found guilty of attempted murder in the shooting death of a teenager says injuries the victim suffered from a second round of bullets should not be a significant aggravating factor in determining the officer's sentence.

Sammy Yatim was already dying from wounds caused by the first volley of bullets legally fired by Const. James Forcillo, lawyer Peter Brauti said Wednesday during the officer's sentencing hearing.

"It deserves the most minimal assessment of actual harm because, from an actual harm perspective, we know it doesn't accelerate or cause his death," Brauti said, as Yatim's mother broke into tears and rushed out of the courtroom.

Brauti is seeking a sentence of house arrest for Forcillo while Crown prosecutors have asked for a prison term of between eight to ten years.

Justice Edward Then, who will decide Forcillo's sentence, noted that there was still "substantial harm" caused to Yatim from the second volley of six bullets fired by Forcillo.

"The only wrinkle here is that by the grace of God it wasn't felt because he had been rendered a paraplegic by the previous bullets," he said.

In July 2013, Forcillo fired two separate volleys --three shots and then six shots -- at Yatim, who had consumed ecstasy and was wielding a small knife on an empty streetcar.

A jury acquitted Forcillo of second-degree murder in the 18-year-old's death, but found the officer guilty of attempted murder for continuing to fire after the dying teen had fallen to the floor. The attempted murder charge pertained to Forcillo's second volley.

Brauti is arguing that certain sections of the Criminal Code involving the mandatory minimum sentence of five years for attempted murder are unconstitutional and weren't meant to deal with cases like Forcillo's.

He said Forcillo's second volley of shots was "excessive" self defence in a situation where Forcillo did not appreciate the difference between a potential threat and imminent threat.

Brauti asked the court on Wednesday to accept what he presented as facts in the case, including an assertion that some of the six shots in Forcillo's second volley were necessary and reasonable while others were not.

He also asked the court to find as a fact that Forcillo saw Yatim flick his knife at him "in a menacing manner" and reasonably believed an attack by the teen was imminent.

Then however, questioned Brauti's conclusion.

"I didn't think it was all that clear and if it wasn't, why am I giving him the benefit of it," said Then, who noted that he'd rather rely on "incontrovertible evidence" of the showdown between Forcillo and Yatim that was captured on cellphone video, which he said showed Yatim was not "an imminent threat" as he lay on the streetcar floor.

"You're asking me to retry this case."

After Then suggested the court focus on the second volley of shots -- which led to the guilty finding against Forcillo -- Brauti asked him to find that Forcillo, after firing the first volley, saw Yatim "rearm himself" with a knife and roll his body over "consistent with an effort to get up off the ground."

Again, Then pushed back.

"Are you saying I have to make a finding of fact when Mr. Forcillo says the rolling of the body is consistent with the effort to get off the floor?" he demanded.

"It falls to you as the sentencing judge to make findings as to whether this is important or not," replied Brauti. "It falls to you as sentencing judge to determine if it's a fact or not. That may involve findings of credibility as well."

Yatim's death triggered public outrage and prompted Toronto's police chief to launch a review of officers' use of force and their response to emotionally disturbed people.

Forcillo's sentencing hearing continues on Thursday.