How chewing gum helped crack a 42-year-old murder case

A detective devised an unusual plan to catch a killer: using chewing gum to secretly collect his DNA. Peter Van Sant reports on the undercover operation that helped solve the cold case murder on the season premiere of "48 Hours."

source https://www.cbsnews.com/video/chewing-gum-helped-crack-42-year-old-murder-case/