Dean Milk Co. v. Madison
Madison, Wisconsin prohibited the sale of milk unless it had been processed and bottled at an approved pasteurization plant within five miles from the central square of the city. This radius was made to make it easier for its health inspectors, but only three plants fell within it. Dean Milk pasteurized its milk in Illinois (although inspected by local officials there) and was thus banned from selling in Madison solely on that basis.
The Wisconsin Supreme Court upheld the five-mile limit.
Did the ordinance violate the dormant commerce clause?
A city cannot discriminate against interstate commerce, even exercising its police power, if reasonable nondiscriminatory alternatives, adequate to conserve legitimate local interests, are available.
Reasonable and adequate alternatives were available. Madison could send its inspectors to the Illinois plants and just charge for the cost incurred thereby. Alternatively, it could just require standards of pasteurization and not require its own inspection at all. One state cannot place itself in a position of economic isolation.
Yes, the ordinance imposed an undue burden on interstate commerce. Reversed.
: Interstate commerce is not being discriminated against. Dean Milk could have pasteurized its milk within the radius despite selling out-of-state milk. Dean's choice of location to pasteurize its milk is what was actually keeping it from doing business, not the ordinance regulating the location.
All health regulations impose some burden on trade, but that does not mean they discriminate against interstate commerce.
No health law has been struck down just because there is another way to safeguard health. This one should not be either unless proven beyond a reasonable doubt that the substitutes would not lower health standards. Neither of the majority's alternatives would assure as pure a supply of milk as the current ordinance, so it should be upheld.