Nagin is the worst possible person any channel should or could have on for advice. He single handily is at fault for most of the deaths in New Orleans. He didn't have enough leadership to force evacuations of the low lying wards.
He also got a pass from the news media for his comment to re-make New Orleans into Choco town. If a white mayor had made those mistakes and racist statements he would have been hung, tarred and feathered.