In the news

The things that make it very hard for us, as an observing public, to make reasonable judgement in this case is the fine detail. We're not really offered an understanding of what has happened. Not only in the lead up to and during the killing, which itself is undisputed in the case, but in the months and years prior to that.

Marine A has made a claim of PTSD which is not an unreasonable or unlikely circumstance to have occured. That's what this whole appeal hinges on. if we are then to presume that it is true then there are things that a judge and jury should consider.

What has caused that PTSD to be manifest and how long has it been present for?
Have their been any opportunities for commanding officers to be made aware of this PTSD and intiate an intervention that takes this person out of active armed duty?
Did, during the operation in which the killing took place, Marine A exhibit behaviour and decision making that should have led his colleagues to believe that he may, under pressure, act in a manner that would breach our adopted rules of combat? If so, where there a safe opportunity to intervene?

There's other questions as well:

Did the armed forces propagate or foster a culture in which mental illness is stigmatised?
Did they foster a culture where exhibition of mental illness was glossed over and service people were compelled to continuing in service that may exacerbate it.
Having attained the rank of Sergeant, should we hold Marine A to a higher standard of behaviour than we would a lower ranking service person?

There are a lot of other questions for which we lack any reasonable evidence or detail from which we could derive an answer. For that reason, I'm very much undecided on this case. I lean slightly in favour of option B simply on the grounds that being unable to answer these questions offers reasonable doubt of option A and reasonable doubt is an important cornerstone of our judical constitution and processes.