H. P. Hood & Sons, Inc. v. Du Mond
The Court struck down New York's refusal to license an additional milk-buying plant for a Massachusetts company, ruling that a state cannot restrict access to its markets simply to shield local dealers and consumers from out-of-state competition.
The decision reinforces a long-standing rule that states cannot use their regulatory powers to wall off their own economies from the rest of the country, even when they frame the restriction as protecting local supply.
“what is ultimate is the principle that one state in its dealings with another may not place itself in a position of economic isolation.”
The majority's core statement that states cannot wall themselves off economically from the rest of the nation.
How it got here: New York's Commissioner denied Hood's license application; the state courts, including the Court of Appeals, upheld that denial; the Supreme Court granted certiorari to review the Commerce Clause challenge.
The Case in Depth
What happened
H.P. Hood & Sons, a Massachusetts company, bought raw milk in New York for same-day shipment to supply Boston's milk market. It already ran three licensed New York receiving plants and sought a license for a fourth, in Greenwich, to attract more producers and shorten some hauls. Competing New York milk dealers objected, and New York's Commissioner of Agriculture and Markets denied the new license, citing risks of destructive competition and reduced local supply.
The question before the Court
Could New York refuse a milk company an extra license to buy milk for shipment to Boston, just to protect local dealers and markets from competition?
The Court's answer
No — the Court ruled that New York could not deny Hood a license to operate an additional milk-buying plant merely because doing so would let Hood compete with other dealers for milk supplies or draw milk away from local markets like Troy. Those grounds were purely economic protectionism, not health, safety, or fair-dealing concerns, and the Commerce Clause forbids states from restricting interstate commerce for that kind of local economic advantage, even without any action by Congress.
The Court also rejected New York's argument that its order coincided with and supported federal milk marketing regulation, finding that the federal Agricultural Marketing Agreement Act was actually designed to keep interstate milk channels open, not to authorize states to close them off. Because New York's justification fell squarely within the category of impermissible local protectionism, the license denial could not stand.
Curious how the Court got there? See the step-by-step legal reasoning →
Why it matters
Businesses that buy raw materials or goods in one state for sale in another can rely on this ruling to challenge state licensing rules designed to keep supplies local. Farmers, milk dealers, and consumers across state lines benefit from open competition for milk, and state regulators must show health or safety reasons rather than economic protectionism to justify limiting market access.
What changes now
The case was reversed and sent back to the New York courts for further proceedings consistent with the Supreme Court's opinion, meaning Hood should be permitted to obtain the license for its proposed Greenwich plant absent some other valid basis for denial. This is a final merits ruling, not a temporary order, and it set a lasting precedent limiting state authority to restrict interstate commerce for local economic protection.
What this does not decide
The Court did not decide whether states may impose health, safety, or fair-dealing conditions on interstate milk buyers, since New York's existing sanitary and financial-responsibility licensing rules were not challenged. It also left open whether Congress could authorize states to restrict interstate commerce for local economic reasons if it chose to do so explicitly.
Concurrences and dissents
Dissent — Justice Black
“All local activities that fall within the scope of this new formula will be free from any regulatory control whatever.”Black's central objection that the majority's rule would leave many local business practices unregulated.
Justice Black argued the majority created a rigid new formula that would leave many local business practices completely unregulated, since Congress could never pass uniform national rules covering every local variation. He viewed New York's law as a legitimate, non-discriminatory effort to prevent destructive competition and protect farmers and consumers, unconnected to any purpose of blocking milk from reaching Boston, and would have upheld it under the traditional balancing approach from Cooley v. Board of Wardens.
Dissent — Justice Frankfurter
Justice Frankfurter argued the case should not be decided as an absolute rule but through a careful balancing of local and national interests, and that the record was too thin to determine how heavily interstate commerce was actually burdened or how important New York's interest in preventing destructive competition really was. He would have remanded the case to the New York courts to develop more facts before deciding the constitutional question.
How the Court got there
The legal reasoning, step by step
- The Court distinguished between a state's broad power to protect public health, safety, and honest dealing in interstate commerce, and its lack of power to restrict that commerce merely to benefit local economic interests — a line the Court had drawn in earlier cases and now applied squarely to this licensing denial.
- The Commissioner's stated reasons for denying the license — that a new plant would divert milk from other dealers and could leave local markets like Troy short during peak demand — were purely economic protectionism, not health or safety concerns, so they fell on the forbidden side of that line.
- The Court examined whether federal milk marketing law shared or occupied this regulatory field with the state, and found that the federal Agricultural Marketing Agreement Act's own provisions were designed to keep interstate milk shipment channels open, not to authorize states to block them for local advantage.
- Because Congress had not authorized states to restrict interstate milk purchases for local economic protection, and the Commerce Clause itself forbids a state from isolating its own economy this way, New York's denial of the license could not stand under either federal statute or the Constitution.
- The Court concluded that allowing states to deny market access this way would invite retaliatory economic barriers between states of exactly the kind the Commerce Clause was written to prevent, so the license denial had to be reversed.
Doctrinal impact
Cases affected by this decision
Reaffirms Baldwin v. Seelig (294 U.S. 511)
The Court relied on and extended Seelig's rule against states using economic isolation to protect local interests.
Distinguishes Milk Board v. Eisenberg Co. (306 U.S. 346)
The Court distinguished Eisenberg because that case involved only incidental burdens like licensing fees, not restrictions aimed at limiting competition.