“The first duty of government is to protect its citizens,” states the National Drug Control Strategy, which also emphasizes that protecting citizens is the goal of U.S. drug policy. However, the report acknowledges that “government must minimize interference in the private lives of citizens,” because protecting citizens also means safeguarding their individual freedom. Sometimes these two goals are in conflict: By outlawing certain behaviors—the use of illegal drugs—drug prohibition necessarily curtails individual freedom.

Advocates of drug legalization believe that restricting the use of certain drugs is an unnecessary, unethical, and unconstitutional infringement on individual liberty. They maintain that the government has no right to prohibit substances just because it believes they are unhealthy or immoral. Adam J. Smith, associate director of the Drug Reform Coordination Network, explains this view: “It is beyond...