He was appointed by Governor Bill Clements to fill a vacancy in the office in November 1987, becoming the youngest Chief Justice since Texas became a state.
", which won widespread attention for its blistering critique of Texas' choice to elect judges by political party without campaign contribution limits.
In each race he defeated one of his Democratic colleagues on the Court, Ted Z. Robertson in 1988 and Oscar H. Mauzy in 1990, who defended Texas' partisan judicial election system and declined to impose campaign contribution caps.
While he was ultimately unsuccessful in this effort, like other Texas chief justices before and since, both the Legislature and the Supreme Court imposed restrictions on the amount, timing and source of campaign contributions to judges during his tenure.
Phillips served as President of the Conference of Chief Justices in 1997-1998, an Adviser of the Federal Judicial Code Project of the American Law Institute, and a member of the Federal-State Relations Committee of the U.S.