An executive order is a directive issued by a government's executive branch, and these legal instruments are used in countries like Liberia, Nigeria, the Philippines, and the United States, as well as in Hong Kong and by India's president. In the U.S., the Constitution does not explicitly authorize them, yet every president since George Washington—who issued the first on June 8, 1789—has used them, with the State Department retroactively numbering them back to Abraham Lincoln's 1862 order. However, the U.S. Supreme Court has ruled that all such orders must be grounded in the Constitution or statute, famously striking down five of Franklin Roosevelt's orders in 1935 and Harry Truman's steel seizure in the 1952 case Youngstown Sheet & Tube Co. v. Sawyer. Meanwhile, Liberia faced backlash over a 2014 order restricting gatherings, but in 2024 President Joseph Boakai used orders to create a war crimes court, while Nigeria saw controversial use under Muhammadu Buhari and other governors during the COVID-19 pandemic. These orders remain in effect until revoked, expire, or are overturned by legislation or judicial review, and Congress can also invalidate them by passing a law or refusing funding.