1. Arrse is anonymous and the military authorities do not have access to real identities any more than anyone else does. Guessing the identity of a poster is not evidence and would be laughed out of any court: anyone initiating AGAI 67 action or formal proceedings would be on extremely dodgy ground.
2. The Human Rights Act allows all of us - including the military - freedom of expression. There are certain restrictions on this, regarding national security, defamation, incitement to racial hatred and so on, but unless one of these has been breached, 'charging' people for posting on Arrse is probably illegal.
3. Even if someone is directly asked: 'Did you post this?', they could and should decline to respond, because we all have a right not to incriminate ourselves.
This may sound like liberal blather, but if Parliament didn't want the Human Rights Act to apply to the military, they could have exempted us. They didn't.
AGAI 67 is not a charge its like the old style extras thats all it is its used for very minor crimes usally lads on tour who fukc up it should not be the first resort ask any rmp and they will help out