Perhaps surprisingly, the one thing missing from today’s oral argument was history. Justices Scalia and Clarence Thomas—both hostile to affirmative action—claim to be constitutional originalists. In other words, they say the Constitution in 2012 should be read to mean precisely what (we presume) the Framers meant in 1787, give or take a few decades.
But the irony is that the authors of the 14th Amendment believed that race-based affirmative action was entirely consistent with that provision. As their rulings on affirmative action show, Scalia and Thomas love history—but only when it suits them.
So how do justices like Scalia and Thomas, who purport to be governed by historical understanding of the Constitution, square these laws with their consistent votes to overturn race-based affirmative action? They don't. Instead, they ignore this history entirely.
In Affirmative-Action Case, History of 14th Amendment Is Inconvenient - The Daily Beast