David Patterson Dyer (February 12, 1838 – April 29, 1924) was a United States federal judge and U.S. Representative from Missouri. He was also the uncle of U.S. Representative Leonidas C. Dyer.Born in Henry County, Virginia, Dyer moved with his parents to Lincoln County, Missouri, in 1841.He completed preparatory studies, went to St. Charles College, studied law in Bowling Green, Missouri, and was admitted to the bar in March 1859.