Trefusis’s family had been seated on the estate above Carrick Roads from which they took their name since the reign of Edward I. His grandfather sat for Truro in 1621. A Puritan, he took the side of Parliament, becoming a leading member of the county committee, and vice-admiral of Cornwall for the Parliament. His father was also a member of the county committee before Pride’s Purge.2Eliott-Drake, i. 255-6, 335, 369; M. Coate, Cornw. in Gt. Civil War, 29, 32, 154, 224.
Trefusis was returned for Penryn at the first general election of 1679, and may also have stood unsuccessfully at St. Mawes. Classed as ‘honest’ by Shaftesbury, he was appointed only to the committee of elections and privileges, and he was absent from the division on the first exclusion bill. He was defeated in September by a court candidate. He died on 5 Nov. 1680, and was buried in Mylor church where a handsome stone statue was erected to his memory. His son Samuel sat for Penryn as an independent Whig from 1698 to 1722 with one brief interval.3CJ, ix. 638.