According to the poll, it looks like most don't know what the graffiti is, what it is saying or meaning.
I heard that the Law Enforcement orgs are following most gangs and before certain gang graffiti is removed, they would like to know what is there and who it is from so they can keep tabs.
Informing them before cleaning would be doing them a favor and favors are returned a lot of times in many different ways, maybe work cleaning up more graffiti or recommendations for work.
I guess if you are about to clean up some graffiti and did not know what it is, if it is just artwork, messages, turf boundries or anything else gang-related it might be a good idea to learn about it because people are sometimes watching.
Roger will tell you what to do in these situations besides telling you about what the graffiti is saying and how to keep yourself safe at all times, even when other people are present.