The Dormant Commerce Clause, or Negative Commerce Clause, in American constitutional law, is a legal doctrine that courts in the United States have inferred from the Commerce Clause in Article I of the US Constitution. The primary focus of the doctrine is barring state protectionism. The Dormant Commerce Clause is used to prohibit state legislation that discriminates against, or unduly burdens, interstate or international commerce. Courts first determine whether a state regulation discriminates on its face against interstate commerce or whether it has the purpose or effect of discriminating against interstate commerce. If the statute is discriminatory, the state has the burden to justify both the local benefits flowing from the statute and to show the state has no other means of advancing