Maj. Tony Tamburro told a military court Tuesday that Maj. Darryl Watts allowed his men to practise with a Claymore C19 anti-personnel mine without any proper training in February 2010 on a firing range four kilometres northeast of Kandahar city.
Cpl. Josh Baker, 24, died when the explosive Claymore, packed with 700 steel balls, raked a Canadian Forces platoon. He was struck four times and one of the steel balls penetrated his chest.
Four others were seriously wounded.
Watts, 44, who was in charge of the range the day of the accident, is charged with manslaughter, unlawfully causing bodily harm, breach of duty and negligent performance of duty.
"We're not alleging Maj. Watts woke up that morning and decided to kill or injure anyone," said Tamburro, who is with the Office of the Judge Advocate General.
"When soldiers went to that range some soldiers had no training on the C19. This is not a case of soldiers being injured or killed in combat. This was not in a firefight.
"This was supposed to be another day on the range."
Tamburro said Watts was not properly trained on the C19, although he did have access to a training manual issued by the Canadian Forces. Tamburro said the soldiers weren't given any classroom training, nor did they have practice devices to work with beforehand.
"They received a briefing on the range and then several members were sent off to fire it for the first time."
Tamburro said the explosion from the C19 was fan-shaped and a number of the soldiers were "not behind cover."
Watts was on the range the day of the blast. He spent time watching the firing or working in his LAV (light armoured vehicle).
He pleaded "not guilty, sir" after each of the charges was read.
The prosecution's first witness was Capt. Christopher Lunney, who pleaded guilty in September to negligent performance of duty in the same blast.
Lunney, 42, was a company commander at the Kandahar Provincial Reconstruction Team at Camp Nathan Smith in Kandahar city.
He was demoted from major to captain and given a severe reprimand for failing to ensure that Watts was properly qualified. Lunney told his court martial he assumed Watts was trained on the device because of his rank at the time.
Lunney testified Tuesday that he was on the range as part of a routine training exercise that was usually held monthly.
He said the first phase of the training went smoothly.
"I had a chance to observe. I didn't see anything out of the ordinary."
Lunney said a short while later he realized a blast had occurred and medical aid was provided and helicopters were called in.
"There was very good scene management," said Lunney.
Once the casualties were transported to Kandahar Airfield, Lunney ordered the area quarantined in advance of an investigation.
Watts's civilian lawyer, Balfour Der, told reporters that his client shouldn't be facing the charges.
"Manslaughter is an overcharge. I think all of the charges are overcharge, because I don't think the man did anything wrong," said Der.
"Darryl Watts was sort of after the fact saddled with these responsibilities that they say make him guilty of manslaughter," Der added.
"At the time he wasn't trained on this explosive device. He was never told he was in charge and yet, after the fact, they're saying he's responsible for the death and injuries that occurred here."
Der suggested it speaks volumes that Watts was promoted to major after the accident.
"He's a damn good soldier ... nothing more."
The trial is expected to last several weeks.
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