James Ley, 1st Earl of Marlborough was an English judge and politician who sat in the House of Commons at various times between 1597 and 1622. He was Lord Chief Justice of the King's Bench in Ireland and then in England, and was Lord High Treasurer from 1624 to 1628. On 31 December 1624, James I created him Baron Ley, of Ley in the County of Devon, and on 5 February 1626, Charles I created him Earl of Marlborough. Both titles became extinct upon the death of the 4th Earl of Marlborough in 1679.

The Lady Chief Justice of England and Wales is the head of the judiciary of England and Wales and the president of the courts of England and Wales.