Who says that the government didn't monitor them well enough to know? They may have known and either condoned it, or just didn't care because of who the potential victims were.
I mean, the thought did cross my mind that part of the issue is that "some of those that work forces are the same that burn crosses", but I didn't necessarily want to open that can of worms and decided to go with the idea that it's a failure not intentional ignorance.