Plenary authority, also known as plenary power, is the complete and absolute power to take action on a particular matter without any limitations or restrictions. The term "plenary" comes from the Latin word plenus, meaning "full." This authority implies full control and often excludes judicial review or limitations on its exercise. In the United States, plenary authority is often granted to certain branches of government or officials in specific contexts. For example, Congress and the President have plenary authority over immigration and citizenship policies. The President also has plenary authority to grant pardons for federal crimes under the U.S. Constitution. Additionally, Congress has plenary authority over Indian tribal affairs. This kind of power typically allows the holder complete control over an issue or domain, with limited or no ability for other entities to challenge or restrict the power's use. In essence, plenary authority means having wide-ranging, broadly construed, and often limitless power within the defined scope of a given authority.
