Corvina is an incorporated city within Los Angeles County, and the Los
Angeles Sheriff's Department provides law enforcement for quite a
number of the cities within Los Angeles County. Cities like Santa
Clarita and West Hollywood have never had police departments, for
example.
Covina does have a police department but I would guess that the LASD
still provides them with support, For example, if a criminal were to
travel from Covina to, say West Covina, he would be in a different
city police district but still within L.A. Country thus the LASD would
still have authority while the city police would not.
--
cheers,
John B.