Dean Milk Co. v. City of Madison
The Supreme Court struck down a Madison, Wisconsin ordinance that required milk sold in the city to be pasteurized within five miles of downtown, ruling that the rule unfairly blocked out-of-state milk from competing even though reasonable alternatives existed to protect public health.
The decision reinforced that cities and states cannot use health regulations to wall off their local markets from interstate competition when less restrictive options, like charging inspection fees or relying on outside health ratings, could achieve the same safety goals.
“one state in its dealings with another may not place itself in a position of economic isolation.”
The Court's core reason for barring Madison from excluding out-of-state milk.
How it got here: The Wisconsin Supreme Court upheld the five-mile pasteurization rule and dismissed the twenty-five-mile inspection claim as non-justiciable; Dean Milk appealed both rulings to the U.S. Supreme Court.
The Case in Depth
What happened
An Illinois company, Dean Milk, sold pasteurized milk from Illinois farms into Madison, Wisconsin. Madison's ordinance barred sale of any milk unless it was pasteurized within five miles of the city center, and separately limited farm inspections to within twenty-five miles. Dean's plants were 65 and 85 miles away, so the city denied it a license even though its milk was Grade A certified in Chicago.
The question before the Court
Could Madison, Wisconsin require all milk sold in the city to be pasteurized within five miles of downtown, even though that kept out-of-state milk from being sold there?
Why it matters
The ruling limited how far local governments can go in using health and safety rules to protect local businesses from out-of-state competitors. It meant milk distributors and other regulated industries operating across state lines could challenge local ordinances that shut them out, even when framed as health measures, if cheaper nondiscriminatory options were available.
What changes now
The five-mile pasteurization requirement was reversed outright as unconstitutional. Because the Wisconsin Supreme Court had not addressed the twenty-five-mile inspection limit on its merits, the Supreme Court vacated that portion of the judgment and sent the case back for further proceedings applying the principles from this decision. The case therefore continued in the Wisconsin courts on the remaining issue.
What this does not decide
The Court did not decide whether the twenty-five-mile inspection limitation was constitutional, sending that question back to the Wisconsin courts. It also did not resolve Dean Milk's separate Fourteenth Amendment argument, since the Commerce Clause ruling was sufficient to decide the pasteurization issue.
Concurrences and dissents
Dissent — Justice Black
“Dean's personal preference to pasteurize in Illinois, not the ordinance, keeps Dean's milk out of Madison.”Black's argument that the ordinance did not actually exclude interstate milk.
Justice Black argued the ordinance did not actually exclude Illinois milk since Dean could simply pasteurize within five miles if it chose to, and that calling the rule 'discriminatory' merely restated the majority's conclusion. He objected to using a 'reasonable alternative' test to strike down a good-faith local health law, arguing the record did not show the suggested alternatives (inspection fees or the Model Ordinance) would keep milk equally safe, and would have upheld the ordinance or at least remanded for evidence on that question.
How the Court got there
The legal reasoning, step by step
- The Court assumed local governments generally may regulate milk sanitation even when interstate commerce is affected, since Congress had not stepped in to occupy the field.
- It found that despite its health rationale, the five-mile pasteurization rule in practical effect excluded wholesome, properly inspected out-of-state milk from the local market, which amounted to discrimination against interstate commerce.
- The Court held that a local law discriminating against interstate commerce cannot stand, even when adopted to protect health and safety, if reasonable nondiscriminatory alternatives adequate to protect the same local interests are available.
- Applying that test, the Court found such alternatives existed: Madison could inspect distant sources itself and charge producers the cost, or adopt a model ordinance provision that accepted milk meeting equivalent standards verified by other health authorities and the U.S. Public Health Service.
- Because less restrictive options could protect Madison's health interests without shutting out interstate milk, the geographic pasteurization limit was an undue burden on interstate commerce and could not be justified as a health measure alone.
Doctrinal impact
Cases affected by this decision
Reaffirms Baldwin v. Seelig, Inc. (294 U. S. 511)
The Court relied on this case's rule against states economically isolating themselves from interstate trade.