The Spanish police is in the process of making a national graffiti database. They are using a new type of software to track the names and pictures of graffiti writers at a national level and not just a city level like it's done now. They feel the need to do this because of the amount of traveling writers do around Spain and why writers that have been caught in their hometown city tend to go to other cities to do graffiti. The software is intended to be used by local police and national police.
News link (Spanish)
Nuevo articulo sobre la elaboración de software para combatir el graffiti en España. Se plantean la colaboración entre policía local, nacional y civil en identificación de tags a un nivel nacional y no solo local como se hace hasta ahora.