Proposition 19 has been defeated by California voters in the 2010 state elections, resulting in more concerns about marijuana related crime and drug violence in the San Francisco Bay Area and the Monterey Bay Area. As a result, police forces in Alameda County, Santa Clara County, San Francisco County, and Santa Cruz County will continue to be burdened by dealing with marijuana possession and distribution crimes, and the courts and jails in these areas will have to deal with overcrowding with persons alleged to have violated non-violent drug possession and distribution crimes.

Additionally, many medical marijuana dispensaries such as those in Oakland, San Francisco, San Jose, and Santa Cruz may be mis-used by people who do not really need marijuana for medical purposes but rather are simply looking for a legal means to purchase cannabis for recreational purposes. Also, the failure of Prop 19 today means that the black market for marijuana sales will continue to flourish in California. Many gangs in California, such as the Surenos and Nortenos, sell illegal marijuana and use the funds to purchase guns, spread violence, and otherwise promote their illegal stronghold over latino communities in California. Further, police forces will continue to be burdened by the onerous task of enforcing laws that target illegal marijuana sales, use and production.

There is no good reason to vote against Proposition 19, even if one opposes marijuana use for any purpose, because there is simply no way to stop people from using the drug. As the history of the Prohibition Era teaches us, efforts to make drugs illegal simply backfire.