Precedent

Precedent is the practice of courts deciding new cases in line with how similar cases were decided before, under the doctrine of stare decisis. It gives the legal system predictability: people and businesses can rely on settled interpretations of the law without every case being argued from scratch. Lower courts are bound by the precedent of higher courts in their jurisdiction; the Supreme Court is not formally bound by its own past decisions, but it treats overturning precedent as a serious step requiring strong justification, not just disagreement with the outcome.

The clearest recent illustration of precedent being overturned is Dobbs v. Jackson Women’s Health Organization (2022), in which the Supreme Court expressly overruled Roe v. Wade (1973) and Planned Parenthood v. Casey (1992), ending nearly fifty years of precedent establishing a constitutional right to abortion. The Dobbs majority argued that Roe had been egregiously wrong from the start and that stare decisis does not require perpetuating a decision built on faulty reasoning; the dissent argued the opposite — that reversing a decades-old right relied on by millions of people is exactly the kind of disruption stare decisis exists to prevent. Both sides agreed the doctrine exists; they disagreed entirely about how much weight it should carry against a case they believed was wrongly decided.

Common misconception: people often treat precedent as an absolute rule that makes overturning old decisions basically impossible. In reality, the Supreme Court has overturned its own precedent well over 200 times across its history; precedent is a strong presumption in favor of stability, not an unbreakable constraint, and the Court has always retained the power to reverse itself when a majority concludes an earlier decision was wrong.