Donald Pomery Lay (August 24, 1926 – April 29, 2007) was an American jurist who served on the United States Court of Appeals for the Eighth Circuit for 40 years, including as chief judge from 1979 to 1982. Born in Princeton, Illinois, Lay was injured playing football while attending the United States Naval Academy, which ended his plans for military service. He earned a bachelor's degree from the University of Iowa in 1949 and received his law degree in 1951.