The Los Santos County Sheriff's Office is a parody of the Los Angeles County Sheriff's Office.  The Sheriff being an elected official, has some autonomy from the other elected officials in the county.  In other words, he's not beholden to which ever political platform the politicians in the region want him to follow. Unlike a city police chief who has to be on the same page as the mayor's office.  The LSSD provides police protection for West Vinewood, Vinewood Hills, Richmond Glenn, Chumash, Davis, El Burro Heights and the mountain range to Highway 68 at the Blaine County Border.  The sheriff also provides security for the court system, and contracts with Bolingbroke Prison.