It starts from the top down and is pervasive, but it is often seeming "little" things at the bottom of the chain that shed light on the pervasiveness of system-wide corruption.  This is why the work Civil Beat does is so valuable and why ThirdRock suggested that Nick "watch his six."  Investigative reporting requires not only a well-developed sense of what is right and what is wrong, but the intestinal fortitude to challenge the system.  Kudos to CB!