In this section, “law enforcement agency” has the meaning stated in § 3–201 of this title. If a law enforcement agency is notified by a medical examiner under § 5–309(d) of the Health – General Article, the law enforcement agency: shall reopen or reinvestigate an investigation involving the death of a victim whose cause or manner of death was amended or corrected to be undetermined or homicide; and may not close a case that was reopened or reinvestigated under item (1) of this subsection until at least 20 years after the law enforcement agency was notified.