Three British army soldiers “had a total disregard for the safety” of their men during a live ammunition training exercise which led to the death of a 21-year-old Corkman.
Ranger Michael Maguire, from Bantry, of Royal Irish Regiment, was one of several soldiers who came under machine gunfire during training in Pembrokeshire in May 2012.
Nigel Lickley QC, prosecuting, told the trial at Bulford that soldiers on one range were firing directly at those on the neighbouring range, who were about 1km away and would have been visible.
Nicknamed "High Tower", the 6' 7" tall Maguire, who had joined the regiment in 2010 and had served a tour in Afghanistan, was shot in the forehead and killed.
Captain Jonathan Price (32), now of the 2nd Battalion, Royal Irish, is accused of the manslaughter by gross negligence of Rgr Maguire through his failure to set up and supervise a safe exercise.
Lieutenant Colonel Richard Bell (45) and Warrant Officer Stuart Pankhurst (40) are both accused of negligently performing a duty during the training exercise held before the soldiers were due to be deployed to Kenya.
"All three men played their part in causing this catastrophe in different ways," declared Mr Lickley, adding that "common sense" meant that machine guns would not be fired directly at "men that you know are there".
All three defendants deny the charges. The trial is expected to last about six weeks. The panel of seven senior officers trying the case will visit the firing range.