 It is common for longtime police officers to refer to a division by the name that area held before merger (e.g., the old fourth district), just as they will sometimes refer to a police officer as being "county" or "city" if they served before merger.Even after the city-county merger became effective in 2003, Louisville Metro Police did not become the sole law enforcement agency in the county.Other than the Jefferson County Sheriff's Office (JCSO), the incorporated cities remaining intact after merger maintain their own police with jurisdiction within those cities.