It most obviously was: "You would never say 'that white man', you would say 'that man'. So why do you say 'that black man' when you mean a black man", I think this is the shortest and most obvious explanation of racism I have ever heard, and I compliment Mr Ba!
So why do you say 'that black man' when you mean a black man. Isn't it self explanatory. I fail to see how this represents racism in any way. If he said something along the lines, "It was probably the black guy", then I would agree it can be interpreted as racist, and probably would be. In this case I see it as unfortunate, inappropriate, but in no way warranted of the response it received. Also this was communication between two officials and it was not directed at any one individual directly.
So this is not racist abuse and I fail to see how could be classified as systemic racism either. The only way this could be interpreted as racist, is if you succumb to the idea, that being labeled as black in any context is inherently racist.