The US Supreme Court has overturned its own precedents 236 times during its 229 years of existence. If you think that sounds high, consider this: Between 1946 and 2016, there were 8,809 decisions made by the high court. During that same time, data from the US Government Publishing Office show 75 overturned decisions. That’s only 1.8% of rulings overturning prior decisions in whole or in part. The justices are strongly in favor of status quo.
Standing by precedent—stare decisis in court parlance—is a well-established doctrine of the US legal system. It is meant to create a stable, consistent rule of law. In 1932, Supreme Court justice Louis Brandeis wrote, “Stare decisis is usually the wise policy, because in most matters it is more important that the applicable rule of law be settled than that it be settled right.” This bold statement has been quoted in 14 subsequent opinions (pdf), yet the court’s actions reveal a cautious appreciation for the need to re-examine prior decisions.
In 1974, a majority opinion stated “The Court bows to the lessons of experience and the force of better reasoning, recognizing that the process of trial and error, so fruitful in the physical sciences, is appropriate also in the judicial function.”
Supreme Court judges just don’t like overruling cases. However, when they do, decisions tend to be overturned within a few decades. Only about 25% of overturned cases were older than Roe v. Wade is today.