RAF policeman Cpl Brent McCarthy, from Telford, and Welsh Guard Lance Corporal Davies were just "in the wrong place at the wrong time".
Speaking at the inquest into their deaths at Oxford Coroner's Court, Lieutenant Benjamin Bardsley said he believed their shooting was an "opportunist event" as no one had been told in advance they were going to be in the area.
They died in what is known as a green- on-blue attack - killed by the Afghan personnel they were mentoring. It is also known as an insider threat.
The insider threat at this time was very, very low.
The risk was deemed as low because it had not happened for a long period of time.
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A largely cloudy but mostly dry start.
A cloudy or misty start to the weekend, although mainly dry with sunny spells developing. Low cloud may linger in some spots.
A largely cloudy start to the weekend but mostly dry start. Through the day, some sunny spells are likely to develop.