In a legal sense, a prohibition is a ban on a particular activity or substance. Prohibitions are usually mandated in response to concerns about safety or ethical issues. Sometimes people use this term in the legal sense to specifically describe bans on drugs and alcohol, although in fact any number of substances can be prohibited by law. Consequences for breaking prohibition can include jail time, fines, and property seizure, if the property is used in illegal activities.
Governments can pass prohibition laws in their legislature and individual judges can issue prohibition orders. With laws, the law is designed to limit availability of a substance or engagement in an activity and to criminalize lawbreaking behavior. For example, a government may prohibit the use, cultivation, or sale of marijuana and provide penalties including fines and jail time for people who violate the law. Such laws are often passed to prohibit dangerous substances or activities that are not deemed to have any redeeming value. For things that pose a danger but also have practical applications, the government may pass limiting laws, such as the controlled substances legislation used to classify and control dangerous medications.
In the case of a court order, a prohibition applies to a specific person and the judge orders the person to desist from a given activity. The court order is issued when someone presents the judge with compelling evidence such as indications that a person's behavior is interfering with the operations of a business. A judge in a higher court can also issue what is known as a writ of prohibition to order a lower court to stop trying a case that falls outside its jurisdiction.
In the case of bans on alcohol and drugs, a prohibition is a form of sumptuary law. Sumptuary laws are laws that are intended to regulate consumption in some form. Historically, they were used to limit everything from the types of fabric people could buy to the accessibility of alcohol. Such laws often have moral overtones; for example, people of lower classes were banned from wearing luxury fibers because it was deemed morally inappropriate.
One of the most famous prohibition laws was passed in the United States with an amendment to the Constitution in the early 20th century. Between 1920 and 1933, alcohol was banned. Despite the best efforts of the government, many Americans continued to drink liberally during Prohibition and some elected officials lobbied vehemently against it. Ultimately, Prohibition was repealed with another amendment.