This relatively minor case is remembered not for the issue supposedly before the Court, but for a footnote that in the eyes of many scholars launched a constitutional revolution.
The case itself involved a challenge to a federal law that prohibited the interstate shipment of ‘‘filled milk,’’ defined in the statute as skim milk ‘‘compounded with . . . any fat or oil other than milk fat.’’ The law had clearly been intended to benefit certain parts of the dairy industry, and Carolene Products, convicted of shipping ‘‘filled milk,’’ challenged it as exceeding Congress’s commerce powers.
Justice Stone practically dismissed this argument out of hand, and in doing so put forward a simple test for weighing the constitutionality of economic regulations. Legislation ‘‘affecting ordinary commercial transactions is not to be pronounced unconstitutional unless in the light of the facts made known or generally assumed it is of such a character as to preclude the assumption that it rests upon a rational basis within the knowledge and experience of the legislators.’’ This ‘‘rational basis’’ test became and remains the basic test for economic regulation; it is the least demanding of all constitutional tests, and few laws have ever failed it.
But immediately after the statement of the rational basis test, Stone inserted footnote four. In it he declared:
There may be narrower scope for operation of the presumption of constitutionality when legislation appears on its face to be within a specific prohibition of the Constitution, such as those of the first ten amendments, which are deemed equally specific when held to be embraced within the Fourteenth.
The note went on to say that such legislation would be subject to a ‘‘more exacting judicial scrutiny,’’ as could laws aimed at particular religions, the integrity of the political process, or at ‘‘discrete and insular minorities.’’
Although Stone did not himself use the term ‘‘strict scrutiny,’’ footnote four led to a new jurisprudence in which economic and other legislation not affecting individual civil rights and liberties would be examined by the courts on a minimal, ‘‘rational basis.’’ If the legislature, either Congress or the states, had the general constitutional power—in this instance, to regulate interstate commerce—and had acted with sufficient reason, the courts would not question the wisdom of the policy.
But when it came to individual rights protected by the Constitution, then the courts would apply a much higher standard. The individual would only have to make out a prima facie case that a right had been restricted, and the burden of proof would shift to the state to prove that the limitation of individual liberty resulted from a compelling governmental interest and had been constructed in the least intrusive manner.
In the 1940s, the Court began applying strict scrutiny to laws affecting First Amendment guarantees— especially speech—and statutes affecting race. As a result of footnote four, lower courts began assuming the role of interpreter of property rights vis-a`-vis the state, and by applying the rational basis test rarely overturned economic regulation. The Court would rarely grant review in such cases. But in the area of free speech and other constitutionally protected rights—and after 1954 laws classifying people on the basis of race—the Supreme Court became the nation’s chief guardian of civil rights and civil liberties.
MELVIN I. UROFSKY
References and Further Reading