They should not operate machinery in this condition. Marijuana may present similar risks, but at present there are no reliable data on its importance in accidents. According to John Stuart Mill's writings, the government should try to control only the aspects of drug use that injure society. In this vein, it makes sense to have laws against driving under the influence of marijuana similar to those governing driving under the influence of alcohol. In other words, driving while on marijuana should be outlawed but not the use of marijuana itself.
Some people believe that marijuana threatens society in a more insidious way.
They argue that it drains workers' energy and makes them less productive. This in turn lowers the vitality of the economy, depressing the overall quality of life. This disease theory holds that legalizing marijuana would make it more widely available and that this would tend to increase its use as well as the use of all kinds of drugs. One of the detriments of tolerating drug use, according to this theory, is that is encourages the use of more and different drugs. Simply put, the number of unanswered questions currently far outnumbers the available answers.