[watwut]

You cant remove gangs, because half of what is called gang is a bunch of young guys living in low socioeconomic area. When then hang around together and some of them is suspect of crime, they are fairly often classified as gang. It does not take much to be classified as gang. And then, any shooting involving them is gang shooting. Similar with drug related shooting, if one of them shoots because he is jealous of girlfriend and there are drugs in his pocket, it is drug related shooting.

Gang membership as traced by law enforcement is not something super formal.