The police des vins were a set of codes and business practices set up in the 13th and 14th century that govern the wine trade within the region of Bordeaux and the use of its port by neighboring areas. The codes were aimed at giving Bordeaux wine a position of dominance over the region and in the English wine market.

The codes had a particular effect on the wines from the Languedoc area, whose wines could not travel down the Garonne river to be sold in Bordeaux until after December 1. This caused those growers to miss the busiest season for trade when prices were at a premium. This sharply disadvantaged the competition for Bordeaux wine. Turgot, the minister of finance under Louis XVI, described the effect of this arrangement in the 18th century: "The conduct of this set of rules, most artfully devised to guarantee to the bourgeois of Bordeaux, the owners of the local vineyards, the highest price for their own wines, and to the disadvantage the growers of all the other southern provinces."