Closing arguments were delivered on Wednesday in the court martial trial of a Calgary reservist charged in the death of another soldier on a training field in Afghanistan in 2010.

Major Darryl Watts held the rank of Captain and was the Officer in Charge of Practice on February 12, 2010 when a range training incident killed Corporal Joshua Baker, 24, and injured Bombadier Dan Scott, Sergeant Michael Mark McKay, Master Corporal William Pylypow and Corporal Wolfgang Brettner.

Watts took the stand on Monday and gave his version of what happened that day.

He admits that he was in charge of the platoon but not of the training exercise that killed Corporal Baker.

Watts told the court that he had never been qualified to run a firing range and had even gone up the chain of command to let others know that fact.

The prosecution says that fact doesn’t matter as the buck stops with the commanding officer.

"The fact that Major Watts was not trained on the C-19 does not abdicate his responsibility as platoon commander," said prosecutor, Major Dylan Kerr.

The defence argued that Watts was not trained on the Claymore devices and that Warrant Officer Paul Ravensdale had been trusted to execute the training that day.

Warrant Officer (now retired) Paul Ravensdale also faces the same charges and another soldier, Capt. (then Maj.) Lunney pleaded guilty to negligent performance of a military duty in relation to the same incident at a court martial on September 13, 2012.

Prosecutor Anthony Tamburro told the court that the soldiers would not have been injured or killed if they were covered during the exercise.

"Command has to mean something. It's not about wearing stripes or going to the Officers Club. It means being responsible to those under your command," said Tamburro.

"Certainly a conviction in this case will reinforce the requirement of commanders at all levels to ensure the safety of their subordinates," said Kerr.

Watts' lawyer Balfour Der says Watts is a ccompassionate and caring officer.

"They didn't train him. They didn't tell him he was going to be using the weapon. They didn't put him in charge of the weapon, so my point is, my position is afterward you don't get to make him responsible," said Der.

Der went on to say that there were five other officers on the range that day, including another major, all of whom had more training with the device than Watts.

He wrapped up his argument for acquittal by saying "This accident has already cost us one good soldier, Don't make it two."

The judge is now taking submissions from the lawyers and will charge the jury at 10:00 a.m. on Saturday.

The five man jury will then be sequestered.

If Watts is found guilty, he could be dismissed from the military or face possible jail time.