TORONTO -- The legalities of self-defence and what constitutes "reasonable" actions are the focus of the Crown's appeal of a Hamilton-area homeowner's acquittal in the fatal shooting of an unarmed Indigenous man in 2016.

Peter Khill, of Binbrook, Ont., was found not guilty in 2018 of second-degree murder in the death of Jon Styres of the Six Nations of the Grand River in southern Ontario.

Khill testified at trial that his training as a military reservist -- he served from 2007 to 2011 -- kicked in when he heard a noise outside his home in the early morning hours on Feb. 4, 2016, then grabbed his shotgun and loaded it. Court heard Khill left his house quietly, did not call 911 or turn on the outside lights, and snuck up on Styres.

He said he saw a shadowy figure leaning into his truck, then the man made a move with his hands -- which is when Khill shot him twice. The lower court heard Styres, 29, was shot in the chest and through the back of his arm and into his chest. He died minutes later.

Prosecutor Susan Reid said Monday at the Court of Appeal for Ontario that the key question in the Crown's case is, "Did the respondent act reasonably in lawful self-defence?"

She said the provisions of self-defence discuss what a "reasonable" person would do in the same situation, and Khill did not act reasonably.

The trial judge made four errors, Reid said, including when he directed the jury to consider Khill's military training as a factor in his self-defence.

"The military training is not a relevant characteristic for a reasonable person," said Reid. "It is relevant in the accused's subjective belief and for how he behaved, but not a characteristic for a reasonable person."

The Crown said the lower court judge essentially created a "reasonable reservist," rather than a reasonable person.

"That is not what the self-defence provisions were intended to address," Reid said. "That is creating too subjective a standard."

One of Khill's lawyers, Michael Lacy, argued that the judge did not make a mistake, saying the Crown in the lower court got the trial it wanted.

"What the Crown is really complaining about is they did not get the results they wanted," Lacy said.

He pointed out that the Crown in the original case did not object to the evidence of Khill's military training. In fact, he said, the Crown was trying to use Khill's military training to help further its case.

"The Crown wanted to make the point that he had military training, then set upon his intruder, tracked him down and executed him in the driveway," Lacy said Monday.

The Crown also argued the trial judge made a mistake in his instructions to the jury by not discussing Khill's role in bringing about the circumstances that led to Styre's death.

Reid said Khill's actions leading up to the shooting should be made explicitly clear to the jury in any self-defence case.

However, Khill's other lawyer, Joseph Wilkinson, argued that Justice Stephen Glithero went on for "page after page" about Khill's conduct leading up to the shooting -- even if he did not explicitly write "the role of" the accused in his charge to the jury.

Khill sat in court on Monday with his wife and friends, while friends and family of Styres packed the other side of the courtroom, most of them wearing orange shirts with the slogan, "Every child matters."

The three-judge panel reserved its decision on Monday.

Khill's acquittal set off outrage among the Six Nations community, which subsequently banned him for life.

Six Nations Chief Ava Hill said at the time the court's decision left the Indigenous community with no faith in the justice system.

The trial echoed a high-profile case in Saskatchewan where a white farmer, Gerald Stanley, was acquitted in the 2016 shooting death of a young Indigenous man, Colten Boushie.

The three-judge panel reserved its decision.

This report by The Canadian Press was first published Sept. 30, 2019.