I don't know the specifics but to keep it short, Sheriffs have jurisdiction in the county. Police jurisdiction are to the city/town limits.

I just saw a video that a Sheriff stated they're elected, which indicates that all deputies are elected and beholden to the public.

There is still going to be corruption in Sheriff department but hopefully less of it and they can be easily removed in theory.

A sheriff works for the county as the executive arm of the county courts. Cops work for the city. A sheriff can act on court orders such as eviction, cops cannot.