John Harris was connected by descent and marriage with some of the principal families in Cornwall. He made his career in local administration and held in succession two minor offices in the duchy. It was probably to the duchy that he owed his return to Mary’s fourth Parliament for Gram-pound, but he may also have benefited from the influence of (Sir) Richard Edgecombe, whose under sheriff he was shortly to become and who owned land adjoining the borough. Neither Harris nor his fellow-Member Richard Chapell joined the opposition to a government bill.3Paroch. Hist. Cornw. iv. 99.
Harris owned much property in Liskeard, held the lease of its rectory and acted as one of the governors of the lands belonging to its parish church. When in Mary’s reign John Connock was accused of wrongfully appropriating the church’s property, Harris took the lead in bringing an action against him in Chancery. Harris died on 26 Aug. 1579 at Lanrest, and his son John succeeded to property in Calstock, Liskeard, Menheniot, St. Keyne and elsewhere in Cornwall.4Duchy Cornw. RO, E6. 1, m. 40v; C1/1356/25; 142/184/20; J. Allen, Liskeard, 134-5.