Served on the Iowa Supreme Court from January 1, 1864, until he resigned December 31, 1869. For two years of this period he was Chief Justice.
Born in Herkimer County, New York, December 25, 1831, and came to Davenport in 1838 with his parents. He was graduated as a Doctor of Medicine in 1850 and practiced that profession briefly at Farming- ton in Van Buren County. He was admitted to the bar in 1852 and elected Judge of the District Court in 1858. In 1870 he became Judge of the United States Circuit Court for the eighth circuit.
Justice Dillon resigned in 1879 to become Professor of Law at Columbia University in New York and a lecturer at Yale, He was author of numerous law books that were universally accepted as authority, and was a member of L'Institut de Droit International. As a leader of the bar of New York he was regarded as one of the most profound jurists of the American bar.
He died in New York City, May 5, 1914.