A Baltimore teenager was sentenced to life in prison Wednesday, more than a year after he accelerated a stolen Jeep and fatally struck a Maryland police officer in a suburban cul-de-sac. Dawnta Harris, 17, was tried as an adult earlier this year and convicted of felony murder in the slaying of Baltimore County police Officer Amy Caprio. A judge in the suburban county that surrounds the city of Baltimore also sentenced Harris to 20 years in prison for burglary.