If politicians can get away with majority of the crimes that would damn an average citizen, what do they have to fear for?

I don't get it. Time after time we read about these politicians that dangle over the grill about to be punished for something, but then they usually don't. Very few do but a lot of the time, they don't. And they seem to get scared about the punishment when they don't factor in the odds and chances that they'll get away with it....