Sir John Ernley (or Ernle) (1464 – 22 April 1520) was a British justice. He was educated at one of the Inns of Chancery from 1478 to 1480 before being admitted to Gray's Inn. By 1490 he was a particularly conspicuous member of the "Sussex circle" gathered around Edmund Dudley. In his home county of Sussex he maintained a substantial legal practice, serving as feoffee, arbitrator, justice and commissioner, and joining the home assize circuit in 1496 and 1497 as an associate, followed by a position on the county bench in 1498. In the 16th century, he acted as a feoffee for Edmund Dudley, and was appointed Attorney General for England and Wales on 12 July 1507 as a result of his influence with Dudley and, as an extension, Henry VII. He was reappointed when Henry VIII came to power and under h