He was the second son of William Southcote and his wife Alice Tregonnell, and grandson of Nicholas Southcote of
Chudleigh, Devon. He was a member of the
Middle Temple, where he was autumn reader in 1556, and again on his call to the degree of
serjeant-at-law, April 1559. In 1553 he sat in Parliament for
Lewes, and then
Steyning. Southcote was appointed justice of the Queen's Bench on 10 February 1563. He sat alongside Chief Justice Sir Robert Catlin during the trial of Robert Hickford on 9 February 1572, a retainer of the
Duke of Norfolk who was indicted for supporting the queen's enemies. He also served as assessor to the peers during the trial of
Thomas Howard, 4th Duke of Norfolk. In addition, he participated in the November–December 1577 conference on the legal approach to handling recusants. In May 1584 Southcote retired and was succeeded by
John Clench. He died on 18 April 1585. ==Family==