Please answer the following question: Alex Kozinski (born July 23 1950) is an American federal appellate court judge. He has served as Chief Judge of the United States Court of Appeals for the Ninth Circuit since November 2007. In addition to his judicial duties Kozinski is an essayist and a judicial commentator. Given a list of categories: company, educational institution, artist, athlete, office holder, mean of transportation, building, natural place, village, animal, plant, album, film or written work, what category does the paragraph belong to?
A:
Office Holder