[3] South Dakota, which allowed 19-year-olds to purchase (raised from 18 years old as result of NMDAA) beer containing up to 3.2% alcohol, challenged the law, naming Secretary of Transportation Elizabeth Dole as the defendant.

The Court established a five-point rule for considering the constitutionality of expenditure cuts of this type: Writing for the majority, Chief Justice William Rehnquist noted that the National Minimum Drinking Age Act clearly met the first three restrictions, leaving only the latter two restrictions worthy of consideration.

Rehnquist wrote that the Congress did not violate the Tenth Amendment because it merely exercised its right to control federal spending.

O'Connor agreed that Congress may attach conditions on the receipt of federal funds, and that the Twenty-First Amendment gives states authority over laws relating to the consumption of alcohol.

She disagreed with the Court's conclusion that withholding federal highway funds was reasonably related to deterring drunken driving and drinking by minors and young adults.