Upon his return to Rockford, Doran served in many administrative, judicial, and pastoral capacities. He returned to Rome in 1975 to complete a Doctor of Canon Law degree in 1978.
After coming back to Illinois, Doran served as chancellor, judicial vicar, vicar for catholic education, and rector of St. Peter's Cathedral in Rockford. In 1986, Pope John Paul II appointed him to be a prelate auditor of the Sacred Roman Rota.