I see your point Helpful Stacker, but I suppose the counter to that is that there was no equivalence between all the parties. If you believe that one side was the force of law and order and the other was terrorists, then surely the former should be held to a higher standard.
Personally, I'm uneasy with the notion of ending investigations and prosecutions of former British soldiers simply by virtue of them being former British soldiers. If crimes were committed, they need to be dealt with.