What is a “Dormant” Commerce Clause?

The commerce clause has traditionally been interpreted both as a grant of positive authority to Congress and as an implied prohibition of state laws and regulations that interfere with or discriminate against interstate commerce. The latter interpretation, of implied prohibition, is the so-called “dormant” commerce clause.

How does the Commerce Clause affect state laws?

Although the Commerce Clause is framed as a positive grant of power to Congress and not an explicit limit on states’ authority, 2 the Supreme Court has also interpreted the Clause to prohibit state laws that unduly restrict interstate commerce even in the absence of congressional legislation—i.e., where Congress is dormant.

What is the Commerce Clause?

The Commerce Clause refers to Article 1, Section 8, Clause 3 of the U.S. Constitution, which gives Congress the power “to regulate commerce with foreign nations, among states, and with the Indian tribes.”