Perhaps the most compelling argument that Grinspoon makes is that criminalization of marijuana use promotes disrespect for the law and is eroding our fundamental civil liberties. Grinspoon states that (in the years preceding 1994) over 300,000 people per year are arrested on charges related to marijuana. This not only causes all levels of government to spend billions of dollars dealing with these arrests, it also promotes disrespect for the law and for those who administer it. In addition, the means used to enforce drug laws have led to significant erosion of civil liberties in the United States including: mandatory drug tests, unwarranted searches and seizures, and the use of the military for civilian law enforcement.
Voth presents numerous arguments against the legalization of marijuana. He maintains that the problems associated with alcohol and tobacco (the legal drugs) provide insights into the possible consequences of legalizing marijuana. Voth suggests that the violence and hardships during Prohibition were actually the result of the Great Depression and not related to Prohibition. He also asserts that drug lobbies will prevent taxes from being levied on marijuana and that lower prices due to legalization will not be sufficient to drive drug dealers out of business. .
Voth discounts the use of marijuana for medical purposes and claims that there have been no credible studies on the therapeutic uses of marijuana. He asserts that there are legal drugs available that can reduce nausea and stimulate appetite as effectively as marijuana. Voth also points to the fact that no medical organizations such as the American Medical Association (AMA) or the American Cancer Society have endorsed or supported marijuana as a therapeutic drug.
Voth asserts that smoked marijuana "contains double to triple the concentrations of tar, carbon monoxide, and carcinogens found in cigarette smoke.