 On March 15, 2005, Johnson was appointed to his state's Supreme Court by Governor Rick Perry to fill a vacancy created by the appointment of Michael H. Schneider to the United States District Court for the Eastern District of Texas by U.S. President George W. Bush.Johnson won voter approval in 2006 to serve the remainder of Schneider's term, and was then reelected in 2008 to a full six-year term.Johnson's term on Place 8 would have run through December 31, 2020.