William Thirning KS (died 1413) was a British justice. He served as a commissioner of the peace in 1377 in Northamptonshire

Northamptonshire

Northamptonshire is a landlocked county in the English East Midlands, with a population of 629,676 as at the 2001 census. It has boundaries with the ceremonial counties of Warwickshire to the west, Leicestershire and Rutland to the north, Cambridgeshire to the east, Bedfordshire to the south-east,...

 and as a commissioner of Oyer and terminer

Oyer and terminer

In English law, Oyer and terminer was the Law French name, meaning "to hear and determine", for one of the commissions by which a judge of assize sat...

 in Bedfordshire

Bedfordshire

Bedfordshire is a ceremonial county of historic origin in England that forms part of the East of England region.It borders Cambridgeshire to the north-east, Northamptonshire to the north, Buckinghamshire to the west and Hertfordshire to the south-east....

 in the same year, as well as a Justice of Assize for Yorkshire

Yorkshire

Yorkshire is a historic county of northern England and the largest in the United Kingdom. Because of its great size in comparison to other English counties, functions have been increasingly undertaken over time by its subdivisions, which have also been subject to periodic reform...

, Northumberland

Northumberland

Northumberland is the northernmost ceremonial county and a unitary district in North East England. For Eurostat purposes Northumberland is a NUTS 3 region and is one of three boroughs or unitary districts that comprise the "Northumberland and Tyne and Wear" NUTS 2 region...

, Cumberland

Cumberland

Cumberland is a historic county of North West England, on the border with Scotland, from the 12th century until 1974. It formed an administrative county from 1889 to 1974 and now forms part of Cumbria....

 and Westmorland

Westmorland

Westmorland is an area of North West England and one of the 39 historic counties of England. It formed an administrative county from 1889 to 1974, after which the entirety of the county was absorbed into the new county of Cumbria.-Early history:...

 in June 1880 before becoming a Serjeant-at-law

Serjeant-at-law

The Serjeants-at-Law was an order of barristers at the English bar. The position of Serjeant-at-Law , or Sergeant-Counter, was centuries old; there are writs dating to 1300 which identify them as descended from figures in France prior to the Norman Conquest...

 in 1383. He was made a King's Serjeant in 1388, and a justice of the Court of Common Pleas

Court of Common Pleas (England)

The Court of Common Pleas, or Common Bench, was a common law court in the English legal system that covered "common pleas"; actions between subject and subject, which did not concern the king. Created in the late 12th to early 13th century after splitting from the Exchequer of Pleas, the Common...

 on 11 April of the same year, becoming Chief Justice

Chief Justice of the Common Pleas

The Court of Common Pleas, also known as the Common Bench or Common Place, was the second highest common law court in the English legal system until 1880, when it was dissolved. As such, the Chief Justice of the Common Pleas was one of the highest judicial officials in England, behind only the Lord...

 on 15 January 1396. Thirning took a leading role in the deposition of Richard II

Richard II of England

Richard II was King of England, a member of the House of Plantagenet and the last of its main-line kings. He ruled from 1377 until he was deposed in 1399. Richard was a son of Edward, the Black Prince, and was born during the reign of his grandfather, Edward III...

 1399, obtaining his renunciation of the throne on 29 September and announcing it in Parliament the following day, before personally announcing the sentence to Richard on 1 October. He continued to be Chief Justice throughout the reign of Henry IV

Henry IV of England

Henry IV was King of England and Lord of Ireland . He was the ninth King of England of the House of Plantagenet and also asserted his grandfather's claim to the title King of France. He was born at Bolingbroke Castle in Lincolnshire, hence his other name, Henry Bolingbroke...

 and was reappointed by Henry V

Henry V of England

Henry V was King of England from 1413 until his death at the age of 35 in 1422. He was the second monarch belonging to the House of Lancaster....

when he took the throne in 1413; he died soon after, as his successor was appointed on 26 June.