It's always disturbing to hear news of Coalition trainers being turned on by their trainees. When you hear of an incident like the one a couple of weeks ago where the five Brits were killed by one of their trainees, it certainly makes you wonder how feasible the end strategy of training more and more Afghan National Security Forces (ANSF...an umbrella term to cover the ANA, ANP, Border Police, and other security agencies within Afghanistan) is. Thankfully, such incidents are rare, but with more and more ANSF out there, we're bound to start seeing more of this. To significantly increase the size of the ANP and ANA they are going to have continue lowering the already low standards for recruits...many are essentially conscripts already.
Currently, ANP members need little more than the recommendation of two local elders in order to get accepted into the police academy - and very shortly after that they are police. There are other requirements, but in a country where few people can read and bureaucratic institutions are lacking, the requirement to be a citizen or not have been convicted of a crime in recent years is not difficult to circumvent.
The ANA has a bit more of a vetting process, but both the ANA and ANP could be easily infiltrated by insurgent sympathizers...and undoubtedly have been. However, having a few bad apples within the units I was embedded with was not really a concern of mine. Not that it did not ever cross my mind, but it was kind of like if I'm going to worry about that then I'm going to drive myself crazy. And my view on it was the good ANA in my unit would protect me from the bad ones if there were any. All in all I trusted them...but, of course, I did what I could to maintain cordial relationships with my guys...not that having a undercover insurgent like you personally is really going to save you if he's dedicated, but it's another reason to develop rapport with them all the same.
Afghans, in general, are not suicidal about their cause and have quite a bit of guile. These incidents where an ANP or ANA member shoots our men are likely to result in the death of the aggressor (though the shooter in the incident mentioned above is still on the loose as far as I know). I would think an infiltrator in the ANA or ANP would be more likely to partake in a more survivable activity, like simply reporting to the insurgents on our patterns and giving early warning of operations. For many reasons, we had quite a bit of difficulty getting the initiative on the enemy during my time - I would not discount the possibility of informers within the ANA contributing to this.
The good news is we have initiatives going on that should help with the vetting and accountability of ANSF forces, and should help over time in getting the bad ones out and out for good. Before I left, we were, with the help of a civilian contractor who was a specialist in working with the biometric data (fingerprints, iris scans, etc.) collection systems in the process of collecting biometric data on our ANA and the local ANP, and putting it into a database. The ANP seemed to think we just needed the biometric data so we could give them an ID card to access the base. Well, our having that data will have longer lasting effects hopefully. I should mention that we were able to collect biometric data on whomever, during checkpoints or otherwise, and we did so from time to time. These systems can quickly link back to databases to identify the person standing in front of you. These are great systems with outstanding potential in a counter-insurgency, but are very underutilized, chiefly because of the painstakingness of the data collection process, in my opinion.