Last September, the Court Martial Appeal Court of Canada entered a finding of not guilty on Major Darryl Watts's conviction for negligent performance of duty. It also ordered a new trial on a conviction of unlawfully causing bodily harm and a second count of negligent performance of duty.
The Director of Military Prosecutions reviewed the Appeal Court's decision and decided not to challenge the ruling.
But a Canadian Forces spokeswoman says whether to hold a new trial is still under review.
"No decision has yet been made by the Director of Military Prosecutions regarding a possible retrial by court martial on the two remaining charges," said Capt. Amber Bineau in an email to The Canadian Press.
"The Canadian Military Prosecution Service is still reviewing the file, and will have to consider if there still exists a reasonable prospect of conviction on those charges, based on the evidence that remains available, and if a retrial would be in the public interest to pursue."
Cpl. Josh Baker, 24, was killed when a C-19 Claymore anti-personnel mine loaded with 700 steel balls misfired and peppered his platoon on a practice range. Four other soldiers were seriously hurt when they were hit by the blast.
The first two tests had gone off without a hitch that day. But during the next one, the ball bearings fired backward, hitting Baker and the others.
Video played at trial showed several soldiers, including Watts, standing around and watching the test. They were not inside armoured vehicles or standing behind them for cover, as set out in military safety regulations.
Watts, who held the rank of captain at the time and was later promoted to major, was placed in charge of the training range in February 2010. He was initially demoted two ranks to lieutenant and given a severe reprimand after his conviction in December 2012.
He has since had his rank of major restored.
Two other soldiers were also convicted for their roles in the accident.
Watts's commanding officer, Maj. Christopher Lunney, pleaded guilty to negligent performance of duty for failing to ensure Watts was properly qualified on the C-19. Lunney was demoted one rank to captain from major and received a severe reprimand.
Warrant Officer Paul Ravensdale, who was running the exercise that day, was found guilty of breach of duty causing death, breach of duty causing bodily harm, unlawfully causing bodily harm and negligent performance of military duty.
He was acquitted of manslaughter, but the now-retired soldier was given a six-month suspended sentence. He also received a fine and was demoted one rank to sergeant.
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