This is terrible for a number of reasons, and I'll skip the discussion on the obvious (how shooting imams really pisses off the locals). After all of the experiences in Iraq and Afghanistan, I do not understand how convoys still end up shooting people around them and just keep moving. That is so 2004. I'm not questioning the decision to fire on the imam's vehicle as I was not on the ground and have no idea what prompted it. Convoys have a tendency to be extremely paranoid of car bombs (rightfully so) and have escalation of force procedures to protect themselves from that threat. While that paranoia can lead to completely unnecessary civilian deaths, they are generally useful and understood by the populace. It seems that this may have been unnecessarily heavy-handed, but again, I wasn't there so I don't know. The automatic investigation into this event will determine that. What bugs me is that they did not stop. Drive-by's should be a thing of the distant past - the convoy had an obligation to stop and cordon off the area to assess the threat, treat any casualties, and interact with witnesses to explain what the hell happened. Otherwise, the conspiracy-minded folk in the area will just go ahead and assume it was an assassination. The other result of this is that any "thorough investigation" won't have local witnesses and will be made entirely of statements of the members of the convoy. I'm going to assume it will be a lot of "I felt an imminent threat so I opened fire" kind of statements - because that's what usually happens (I may be proven wrong here, but I've never seen anything to the contrary) and is actually quite less than thorough.
The second problem I see here is the ISAF statement. Well no kidding this is tragic and everyone regrets it. ISAF should have publicly taken that convoy to task (they didn't have to identify them at this point) for not stopping and doing those three things listed above. We were told to expect more candor from ISAF when drone strikes kill civilians, I guess I expected that to include when convoys do stupid things, too. How silly of me. I understand mea culpas don't always make things right, but the bland statement that was made borders on obfuscation of the facts.
With the command's insistence on protecting civilians as its highest priority, both the actions of the patrol and the comments from ISAF violate the Chairman's "say-do" gap, in my opinion at least. It seems ISAF still has a long way to go in understanding the lessons learned in the past eight years.