Sir William Oliphant, Lord Newton (1551 – 1628) was a Scottish judge. Admitted as an advocate in 1577, he became an Advocate Depute in 1604. He gained favour of James VI by throwing up his brief for the six ministers in 1606. He was appointed a lord of session from 1611-26, with the judicial title Lord Newton and was Lord Advocate from 1612 to 1626. He was appointed a member of new High Commission court in 1615. He was responsible for the present procedure of examining witnesses in court.