I understand. At some point we have to face the reality that there will rarely be cooperation with police because the perps are related to many in the ‘hood. If your son brings home the bacon by selling drugs, how likely is it that you or any of your friends are going to turn him in? Also, how could the cops protect someone who does?
Worse: if your son is in a gang, you can't inform on any of his fellow gang members. If you inform on a member of some other gang, you invite retaliation against your family.