Well there was Cool C and Steady B... but they murdered a Philly police woman.
The funny thing about Cool C and Steady B were that they weren't 'gangsta rappers' by anyone's definitions. Their hits included songs like "Going Steady" (yes, as in dating someone going steady), "Girls Gonna Getcha", and "Glamorous Life". Very old school, pre-gangsta rap but they were retards and felt the need to rob a PNC bank in 1996.
The faces of cop-killing rappers:
Go figure, right?