"It is also important to point out that in no Western country is a user at much risk of being criminally penalized for using marijuana. The rates of arrest for past-year marijuana users in Western countries are typically less than or equal to 3 percent (Kilmer, 2002; Room et al., 2010). More important, almost none of those convicted of simple possession is incarcerated or receives a fine exceeding $1,000 (Pacula, MacCoun, et al., 2005)."

Source

Kilmer, Beau; Caulkins, Jonathan P.; Pacula, Rosalie Liccardo; MacCoun, Robert J.; Reuter, Peter H., "Altered State? Assessing How Marijuana Legalization in California Could Influence Marijuana Consumption and Public Budgets" Drug Policy Research Center (Santa Monica, CA: RAND Corporation, 2010), p. 13.
http://www.rand.org...