Scott Bales, chief justice of the Arizona Supreme Court, announced he is retiring at the end of July.
Bales, named to the court in 2005 by Democrat Gov. Janet Napolitano, is currently the longest-serving member of the court. He is just completing five years as the chief justice.
Tuesday's move means Gov. Doug Ducey will get to name a fifth member of the court.
The Commission on Appellate Court Appointments just sent Ducey a list of five nominees to fill the slot of John Pelander who stepped down at the end of last month. Bales' announcement now requires that panel to start the process anew.
Ducey already has named political independent Clint Bolick to the court, along with Republicans John Lopez and Andrew Gould.