I also learned some new lingo today. One of his customers apparently sent a text message asking him for "prices on clear and Negra." I knew that "clear" meant methamphetamine; thank you for that, Breaking Bad (even though Walt's meth was famously blue). But I had to look up what "Negra" meant. (Judge Nelson's opinion mentioned that it had something to do with drugs, but not precisely what.)
I get it now. Makes sense. "Negra" is black (which I already knew; thank you, Negra Modelo). So with drugs, it means heroin; specifically, black tar (or brown) heroin.
Now you know too. (If you didn't already.)