Hart studied law in Warren, Ohio. On August 12, 1851, he was admitted to the legal profession and practiced in Ravenna, Ohio. 1861 to 1864 he was prosecuting attorney of Portage County. In the years 1865, 1872 and 1873 he was a member of the Senate of Ohio. Thereafter, he practiced from 1873 to 1875, a tenure as Lieutenant Governor (Lieutenant Governor ) of Ohio.
Hart was elected as a Republican to the 48th Congress and represented there on 4 March 1883 to 3 March 1885 the state of Ohio in the U.S. House of Representatives. His attempt to be selected in the 49th Congress failed.
He died in 1910 in Washington DC and was buried in the Maple Grove Cemetery in Ravenna.