"BTW, since he's elected by the people of Travis county, but has jurisdiction over the whole state, isn't that unconstitutional?"
Apparently not - there's some quirk in the state Constitution, I suppose:
"Besides his traditional role as prosecutor, Earle, as Travis County D.A., has the unique duty of heading up the state's Public Integrity Unit."
http://archive.jdedman.com/100396.htm