They hired Graffiti Tracker, a web based graffiti analysis service. After County personnel photograph and upload pictures of graffiti, analysts identify whether it is gang related and report back to the county. In addition analysts can match distinguishing characteristics of graffiti from several locations to a particular vandal, tracking trends and migration, and consolidating data for the county to prosecute vandals.
The county was able to get nearly $90,000 in restitution from one family of one youth who sprayed about 100 pictures of his "art". If the 18 month pilot program pays off, the county will move to make it permanent. (Sound like Sand Diego County has some type of Uni-Gov that I believe will be one of new City Manager, Patrick Urich's major project.
Source - County News, March 14, 2011 issue. Read the whole article.