Rather single minded response, I'm not sure what you are asking. To spell it out, asking who is paying his salary is to ask a number of questions (I think you've immediately assumed conspiracy):

- If it is the people/government are they getting their money's worth?

- If he's taking backhanders is it corruption?

- If it's neither of these what is the motivation for this sort of justice?

Perhaps I don't understand the make-up of the federal government in the US but it's presumably has to answer to the citizens.