OECD has released a report on Anti-spam Law Enforcement

"Successful enforcement of anti-spam law serves as an economic disincentive to spammers by imposing fines and penalties which undermine their profits, provides a state-sponsored mechanism for protection and redress to victims of spam-related consumer fraud, and vindicates the privacy rights of spam recipients. Ultimately, an increased enforcement presence may help restore trust in e-mail systems that has been eroded by spam."

For the full report (PDF), click here.