The United States courts of appeals are considered among the most and courts in the United States. They have the ability to set legal precedent that affect millions of Americans. The United States courts of appeals have strong influence on U.S. law. The U.S. Supreme Court chooses to review less than 1% of the more than 10,000 cases filed with it ly. This means the United States courts of appeals makes the final decision in most federal cases. The Ninth Circuit in particular is very influential. It covers 20% of the American population.