When crime surged in 2015 after the Freddie Gray protests, Baltimore police were more determined than ever to rack up more arrests and seize more illegal guns from the streets. A new book chronicles how that empowered cops on the ‘Gun Trace Task Force’--some of whom had been planting evidence, making illegal arrests and robbing drug dealers for years--to step up their own illicit activities. It took a federal indictment to shut down the Gun Trace Task force in 2017. We ask why the authors say prosecutors and police commanders looked away.