Cal. Gov't Code § 8594.14
(b)
(4) Upon activation of an Ebony Alert, the Department of the California Highway Patrol may use a changeable message sign if both of the following conditions are met:
(c) A law enforcement agency may request that an Ebony Alert be activated if that agency determines that there is information available that, if disseminated to the public, could assist in the safe recovery of the missing person, and the following conditions are met regarding the investigation of the missing person:
(2) The investigating law enforcement agency has used all available local resources and at least one of the following conditions are met:
(A) The law enforcement agency determines that the person has gone missing under unexplained or suspicious circumstances, including circumstances that indicate any of the following: