Sarah Everard.Serving Met Police officer Wayne Couzens falsely arrested Sarah before raping and killing her, then burning her body in woodland.He was sentenced to life in prison this week.Police Scotland say the introduction of a new system will allow worried members of the public to check with the control room and verify if police officer approaching them is a real cop.A statement released tonight reads: "The move follows the understandable public concern surrounding the horrendous murder of