Judicial Administration and Improvement Act of 2019 This bill divides the U.S. Court of Appeals for the Ninth Circuit into two judicial circuits: (1) the Ninth Circuit, and (2) a new Twelfth Circuit. The Ninth Circuit is composed of California, Guam, Hawaii, Oregon, Washington, and Northern Mariana Islands. The new Twelfth Circuit is composed of the following states: Alaska, Arizona, Idaho, Montana, and Nevada.