First thing to note is that he apparently has Aspergers (only according to the media and I'm not making any assumptions, I'm not a Doctor but I imagine it may have had some affect on the whole drama) - I'm guessing the reason for the light/deferred sentence and the requirement for mental health services is that the court determined he didn't have the capacity to determine what he did or the consequences of it... I know people will think 'he knew what he was doing' but none of us were in his mind nor examined all the evidence.
Second thing and the most alarming IMHO is that he either left or was dismissed from his job at VA YET, according to media reports he still had his uniform... how the HELL did that happen... if it did then it's bloody slack... has no one in that organisation heard of PS1771??? Oh, sorry, forgot, most of the people making decisions either have no airline background or came straight to DJ from High School...
In any case, no employer can completely screen or predict what an employee will be like but considering the prolonged rubbish this one goes to with recruitment and the associated processes, maybe some reality needs to come into the process and there needs to be a tick box on an exit form "Uniform Returned - Yes/No"...