Who is over the sheriff of a county?

Answer 1

The State is above the county sheriff. The county sheriff pretty much means they have the satisfaction of being sheriff. Then above the state is Federal. Which is pretty much the FBI and Other stuff like that

Answer 2

The people, i.e. the voters. A county sheriff (as opposed to a police chief) is virtually always an elected official and is only partly subject to county supervisors and councils. In many cases, he is also the tax collector, with additional political power.

Like other elected officials, he is still subject to rulings of local and state courts.