List of landmark court decisions in the United States

The following is a partial list of landmark court decisions in the United States. Landmark decisions establish a significant new legal principle or concept or otherwise substantially change the interpretation of existing law. Such a decision may settle the law in more than one way:

In the United States, landmark court decisions come most frequently from the Supreme Court. United States courts of appeals may also make such decisions, particularly if the Supreme Court chooses not to review the case or if it adopts the holding of the lower court. Although many cases from state supreme courts are significant in developing the law of that state, only a few are so revolutionary that they announce standards that many other state courts then choose to follow.

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