As used in this chapter: “Critically missing adult” means an adult, including an adult who has a developmental disability, intellectual disability, or mental illness as those terms are defined in § 37.2-100, 18 years of age or older whose whereabouts are unknown and whose disappearance poses a credible threat as determined by a law-enforcement agency to the health and safety of the adult and under such other circumstances as deemed appropriate by the Virginia State Police. “Critically missing adult alert” means the notice of a critically missing adult provided to the public by the media or other methods under a Critically Missing Adult Alert Agreement. “Critically Missing Adult Alert Agreement” means a voluntary agreement between law-enforcement officials and members of the media whereby an adult will be declared missing, and the public will be notified by media outlets, and includes all other incidental conditions of the partnership as found appropriate by the Virginia State Police. “Critically Missing Adult Alert Program” means the procedures and Critically Missing Adult Alert Agreements to aid in the identification and location of a critically missing adult. “Media” means print, radio, television, and Internet-based communication systems or other methods of communicating information to the public.