On Nov. 6, voters in Colorado and Washington approved ballot initiatives to legalize the possession and sale of marijuana, while a similar initiative in Oregon failed. The possession and sale of marijuana is still a violation of the federal Controlled Substances Act, and it remains to be seen whether the Justice Department will modify its enforcement priorities in response to these initiatives.

Colorado and Washington will now attempt to regulate and tax cannabis in a manner similar to the regulation and taxation of tobacco and alcohol. Advocates of these initiatives claimed that marijuana legalization will lead to increased revenue for the states and decreased drug-related crime, among other "benefits." A closer look at the issue, though, shows that the opposite is true and that the real social costs will dramatically outweigh any elusive benefits.

Legalizing the sale and possession of marijuana will result in a steep reduction in the street price of marijuana since, according to Dr. Rosalie Pacula of the RAND Corp., "prohibition raises the cost of production by at least 400%." Therefore, if we assume marijuana is valued at $300/ounce on the black market, it will likely be worth $75/ounce after the initiative is approved, thereby reducing any potential tax revenue from the sale of "legal" marijuana.

While the reduction in price will limit any potential tax revenues, there is no question that the price reduction will lead to a dramatic increase in black market sales in states where it remains illegal, as drug dealers tote large quantities of the drug across state lines to take advantage of the large price differential. The turf wars among drug dealers for control over these new lucrative markets and access to growers will not end - if anything they will worsen.

Even in states where marijuana is legalized only for so-called medical purposes, it is easy to see a correlation between increases in use of the substance and increases in crime. For example, in Los Angeles, police report that areas surrounding cannabis clubs have experienced a 200% increase in robberies, a 52.2% increase in burglaries, a 57.1% increase in aggravated assault, and a 130.8% increase in burglaries from automobiles.

Moreover, the scientific literature is clear that marijuana is addictive, its use significantly impairs bodily and mental functions and is associated with cancer, strokes, heart disease, birth defects, and a host of other serious medical conditions. The attendant added costs associated with these conditions would likely swamp any revenues derived from the sale of "legal" marijuana. And a recent study conducted by researchers at Duke University's Center for Child and Family Policy shows that teens who frequently smoke marijuana are more likely to suffer a long-term drop in IQ.

In addition to marijuana's harmful effects on the body, the expected increase in health costs associated with its use, and its relationship to criminal conduct, marijuana is a gateway drug that can, and often does, lead users to more dangerous drugs. Prosecutors, judges, police officers, detectives, parole or probation officers and even defense attorneys know that the vast majority of defendants arrested for violent crimes test positive for illegal drugs, including marijuana. They also know that marijuana is the starter drug of choice for most criminals.

Legalizing marijuana is a bad deal all around and will serve little purpose other than leading to increased addiction, crime, societal disorder and adverse health consequences and costs.

A former prosecutor and defense attorney, Charles "Cully" Stimson is now a senior legal fellow at The Heritage Foundation.