Bailiwick is an old English legal term and is a compound of baile, which is now bailiff, and wic, meaning a farm or dwelling.
From the mid-fifteenth century the word meant “under a bailiff’s jurisdiction”, which leads us to the sheriff.
During monarchial rule, each English shire had a reeve who acted as chief magistrate for the district.
When the title “shire reeve” crossed the Atlantic it became “sheriff.”