Cupp is a former Justice of the Ohio Supreme Court. He was elected November 7, 2006 to a six-year term and was sworn in on January 2, 2007. His term expired January 1, 2013 following his election loss to William O'Neill. Between Cupp's election and the death of Chief Justice Thomas Moyer in 2010, all the Justices of the Court were Republican. Before joining the Ohio Supreme Court, Cupp gained appellate judicial experience as a judge on the Ohio Court of Appeals (Third Judicial District) from 2003 to 2006.