There's nothing new about handgun bullets designed for improved penetration - my Western Ammunition Handbook devotes several pages to handgun ammo designed for police that would penetrate car bodies and stop the fleeing criminals inside - the date on the handbook is 1947, making it appreciably older than I am. An example round was a 158 grain .357 Magnum load with a conical brass or bronze point - though not exactly common, until the 1980's "Cop Killer" nonsense this load was frequently found on store shelves labeled as "Metal Piercing." Supposedly it was the round Elgin Gates used to stop a Cape buffalo on an African safari by shooting it between the eyes. Pictures of an "unknown, exotic" bullet used to assassinate Swedish prime minister Olaf Palme in 1986 looked like one of these projectiles - though no armor or metal was penetrated. I'm unaware of it ever being used to penetrate an officer's Kevlar vest.