When Chief Justice Sir John Cavendish was killed in the Peasants' Revolt in 1381, Tresilian was appointed to take over the position.

[2] He pressured jurors into giving up names of suspects,[3] and to maximise sentences, contrived to have charges presented as felonies rather than trespasses.

[4] There was a widespread belief in the localities that royal retribution had gone too far, and that reform of government was necessary as well as punishing the rebels, to prevent further uprisings.

The king resented this infringement of his royal prerogative and, in the so-called 'questions to the judges', he received legal backing for the position that the commission was unlawful.

On 17 November 1387, Tresilian was among a number of royal loyalists who were charged with treason by the group of noblemen known as the Lords Appellant.

His land was forfeited at his death but, his son's objections notwithstanding, much of it was regained by John Hawley the elder, a merchant and privateer from Dartmouth who purchased the estates from the Crown.