CALGARY -- A Canadian Forces reservist has avoided jail for his role in a deadly training accident in Afghanistan three years ago.

But Maj. Darryl Watts is being demoted by two ranks to lieutenant and is to receive a severe reprimand.

He was convicted at a court martial in Calgary late last year of unlawfully causing bodily harm and negligent performance of military duty.

"I do not consider dismissal from the Canadian Forces to be appropriate. I believe the offender can continue to make a contribution to the Canadian Forces," Cmdr. Peter Lamont, who acted as judge at the court martial, said as he delivered the sentence Wednesday.

"He can continue to be a highly effective officer," added Lamont, who pointed out rank can also be regained.

Watts stood at attention during sentencing. There was no visible reaction.

Cpl. Josh Baker was killed and four other soldiers were injured when an anti-personnel mine misfired and shot hundreds of steel ball bearings in the wrong direction.

The prosecution had argued that Watts, who was the platoon commander, didn't enforce safety standards and abdicated his duty as leader when he handed over responsibility for safety on the training range to Warrant Officer Paul Ravensdale.

Prosecutors wanted Watts to spend 18 months in jail.

The defence suggested Watts's blame worthiness was on the low end of the scale, since no one could have predicted what his lawyer called a "freak accident."

"He should only receive a very minimum sentence ... a reprimand," defence lawyer Balfour Der said after a sentencing hearing last month.

"Maj. Watts was found guilty, but it's as marginal as it can be," he added.

Lamont disagreed with both.

"I have concluded the sentencing position of the prosecution is too severe," he said.

But he dismissed Der's request for a simple reprimand as "wholly insufficient to address the degree of responsibility of the offender.

"Maj. Watts was directly responsible for all members of his platoon," he said.

The court martial heard that the range was divided into four training sections that day. The first two tests of the anti-personnel mine went off without a hitch. But when the second firing occurred, the ball bearings fired backwards, hitting Baker and the others.

Videos show several soldiers, including Watts, standing around watching the test. They are not inside armoured vehicles or standing behind them for cover as set out in safety regulations.

Der said a harsh sentence could destroy his client's life. Watts works as a senior firefighter with the Calgary Fire Department as his regular day-to-day job.

"Jail would likely end his career as a firefighter. It would end his career as a military officer."

Watts's commanding officer, Maj. Christopher Lunney, pleaded guilty in September to negligent performance of duty, was demoted to captain and given a severe reprimand.

Ravensdale, who has since retired, was convicted last week of unlawfully causing bodily harm, two counts of breach of duty and one count of negligent performance of military duty. He has yet to be sentenced.