In 1919, during the Prohibition period, alcohol was banned in the United States with the passage of the 18th Amendment to the United States Constitution. But in 1933 the 21st Amendment to the U.S. Constitution repealed the 18th Amendment, and gave states the power to enact their own laws regarding the production, distribution, and sale of alcohol.

Today, each state—and in some cases, each municipality or county—has its own regulations regarding the sale and shipment of all alcoholic beverages. When shipping alcohol across state borders, both the law of the state from which the shipment is made and the law of the state in which it is received are relevant. And the commercial carriers such as UPS, FedEx, and DHL only ship alcohol to and from licensed manufacturers, distributors, sellers, and importers.

In California, the regulation of alcohol is governed by both state statutes and the California Department of Alcoholic Beverage Control (ABC). The ABC provides licenses for the manufacture, distribution, and sale of alcoholic beverages within the state and enforces the laws related to alcohol. California allows for direct-to-consumer shipping of wine from wineries and, under certain conditions, from retailers as well. However, when it comes to shipping alcohol across state lines, both California's laws and the laws of the destination state must be adhered to. This means that licensed entities in California can ship alcohol out of state only if it is legal to do so in the recipient state. Similarly, alcohol can only be shipped into California by licensed entities that comply with California's regulations. Commercial carriers like UPS, FedEx, and DHL have policies in place that restrict alcohol shipments to and from licensed parties only, in accordance with federal and state laws.