A Canadian Forces captain is going back to court to learn his fate for shooting an unarmed and wounded insurgent after a battle in Afghanistan.

But first a military judge will decide Monday on whether the sentencing provisions of the National Defence Act violate the Charter of Rights and Freedoms.

In the early days of Capt. Robert Semrau's trial, his lawyer had suggested that because the available punishments under the defence act aren't the same as the Criminal Code, it violated his client's rights.

But a decision on the issue was put off until the five-member military panel hearing the case had reached its final judgement.

One week ago, they found Semrau guilty of disgraceful conduct for shooting the Afghan fighter in the aftermath of a heated battle in the Helmand district of Afghanistan in October 2008.

The range of sentencing options don't include criminal court punishments like house arrest or community service.

Instead, he could serve up to five years in jail, part of which would be served in a military prison and part in a civilian facility.

The court could also sentence him to a lesser punishment, including dismissing him from the military with disgrace.

On a Facebook page devoted to supporting Semrau, his brother asked people to write letters to the judge saying they stand behind him.

"Tell the judge what you think about Rob, despite this conviction ... what kind of person he is, what kind of colleague he is, what kind of soldier he is," Bill Semrau wrote.

"We need to avoid telling the judge not to put Rob in jail, or that you think he is innocent of all the charges. What we need to do is tell the judge what kind of man he is."

The 36-year-old was part of a team of Canadian soldiers assigned to the Afghanistan National Army as mentors.

Semrau had faced criminal charges in the case as well, for second-degree and attempted murder.

The panel found him not guilty of those charges as well as not guilty on a defence act charge of negligent performance of a military duty.

A challenge in the case was that the insurgent's body was never recovered, leaving the prosecutors without the forensic evidence to prove a murder had actually taken place.

"We proved the fact that he shot and wounded an unarmed man, that's what we proved beyond a reasonable doubt," military prosecutor Lt.-Col. Mario Leveillee said after the panel read out its verdict.

"Why they reached the verdict they reached, I cannot say."

Over the four-month trial, which included time in Afghanistan, the court heard from a dozen witnesses.

The testimony included descriptions of what Semrau was alleged to have said in the moments after he fired two rounds in the direction of a badly wounded insurgent.

The man had been strafed by a U.S. helicopter gunship and witnesses described devastating injuries, including a severed leg and a gaping hole in his abdomen.

Court heard that after shooting the man, Semrau told fellow officers he had done it to put him out of his misery.

Semrau didn't testify.