The office of Chief Justice of the Supreme Court in the United States is traditionally held by the head of the judiciary, who oversees the court's functions and leads its deliberations. As of my last update, the Chief Justice is John Roberts, who was nominated by President George W. Bush in 2005. The Chief Justice's responsibilities include presiding over oral arguments, guiding the court in decision-making, and ensuring the effective administration of justice. Additionally, the Chief Justice plays a crucial role in shaping judicial policy and can influence the court's direction, particularly in cases with significant societal implications.