The primary constitutional principle at the heart of this case is the doctrine of equal protection. The concept of equal protection is deeply rooted in our national and state history, but that history reveals this concept is often expressed far more easily than it is practiced. For sure, our nation has struggled to achieve a broad national consensus on equal protection of the laws when it has been forced to apply that principle to some of the institutions, traditions, and norms woven into the fabric of our society. This observation is important today because it reveals equal protection can only be defined by the standards of each generation.

The process of defining equal protection, as shown by our history as captured and told in court decisions, begins by classifying people into groups. A classification persists until a new understanding of equal protection is achieved. The point in time when the standard of equal protection finally takes a new form is a product of the conviction of one, or many, individuals that a particular grouping results in inequality and the ability of the judicial system to perform its constitutional role free from the influences that tend to make society’s understanding of equal protection resistant to change. As Justice Oliver Wendell Holmes poignantly said, “It is revolting to have no better reason for a rule of law than that so it was laid down in the time of Henry IV. It is still more revolting if the grounds upon which it was laid down have vanished long since, and the rule simply persists from blind imitation of the past.