The Supreme Court adopted a heightened level of judicial scrutiny when dealing with gender-based classifications alleged to be discriminatory.
Oklahoma law permitted eighteen-year-old women to purchase beer with 3.2 percent alcohol but required men to be twenty-one years old for the same privilege. Curtis Craig and a licensed vendor challenged the law. The state had statistical evidence demonstrating a reasonable basis for the law. The Supreme Court had recognized since 1971 that the equal protection clause of the Fourteenth Amendment applied to classifications based on sex. The issue in the Craig case was whether the law should be evaluated according to the rational basis test or the very demanding standard of strict scrutiny, as used in classifications based on race.
By a vote of seven to two, the Court found that the Oklahoma law was unconstitutional. Writing for the majority, Justice William J. Brennan, Jr.,
Equal protection clause
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