The Carthusian martyrs are those members of the Carthusian monastic order who have been persecuted and killed because of their Christian faith and their adherence to the Catholic religion.
Under the law of the United Kingdom, high treason is the crime of disloyalty to the Crown.
 Offences constituting high treason include plotting the murder of the sovereign; committing adultery with the sovereign's consort, with the sovereign's eldest unmarried daughter, or with the wife of the heir to the throne; levying war against the sovereign and adhering to the sovereign's enemies, giving them aid or comfort; and attempting to undermine the lawfully established line of succession.
 Several other crimes have historically been categorised as high treason, including counterfeiting money and being a Catholic priest.
Blessed John Haile was an elderly secular priest who was vicar of Isleworth Middlesex in the early 16th century; his significance in history, like that of many of the English martyrs, begins only with the events which led to his death.
 He was a fellow of Kings Hall, Cambridge, and is said to have lived an edifying life.
 He held the benefice of Chelmsford in Essex before his promotion to Isleworth on the 13th of August, 1521.
 He was arrested in March 1535 by King Henry VIII's men and accused of the crime of treason for speaking against the King's divorce and remarriage.
 The information was laid by another priest, Fern of Teddington who was also convicted of treason, but received a pardon.
 John Haile was executed at Tyburn on the 5th of May, 1535, together with the first Carthusian Martyrs and the Bridgettine priest St Richard Reynolds, the confessor of nearby Syon Abbey.
 He was the first secular priest to suffer for the Catholic Faith under King Henry VIII and be recognised as a martyr and he was beatified on the 29th of December 1886 by Pope Leo XIII with 53 others.
To be hanged, drawn and quartered was a penalty in England for men guilty of high treason.
 The convicted were fastened to a wooden hurdle which was dragged by horse to the place of execution.
 Once there, they were ritually hanged (almost to the point of death), emasculated, disembowelled, beheaded and quartered (chopped into four pieces).
 As a warning against further dissent, these remains were often displayed at prominent places, such as London Bridge.
 For reasons of public decency, women convicted of high treason were burnt at the stake.
The Carthusian Martyrs of London were the monks of the London Charterhouse, the monastery of the Carthusian Order in central London, who were put to death by the English state in a period lasting from the 4 May 1535 till the 20 September 1537.
 The method of execution was hanging, disembowelling while still alive and then quartering.
 The group also includes two monks who were brought to that house from the Charterhouses of Beauvale and Axholme and similarly dealt with.
 The total was 18 men, all of whom have been formally recognized by the Catholic Church as true martyrs.
The Treason Act (Ireland) 1765 (5 Geo 3 c. 21 (I.)) was an Act of the former Parliament of Ireland which gave defendants in trials for high treason under the Treason Act 1351 the right to be represented by counsel and the right to be given a copy of the indictment in advance of their trial.
 (These rights had been available under English law since the Treason Act 1695, and under Scottish law since that Act was extended to Scotland by the Treason Act 1708.)
 The Act's long title was "An Act for the better regulating of trials in cases of high treason under the statute of the twenty fifth of Edward the third" (sic).
 It was repealed by the Treason Act 1945, by which time it had long been obsolete.
To be hanged, drawn and quartered was from 1351 a statutory penalty in England for men convicted of high treason, although the ritual was first recorded during the reign of King Henry III (1216–1272).
 Convicts were fastened to a hurdle, or wooden panel, and drawn by horse to the place of execution, where they were hanged (almost to the point of death), emasculated, disembowelled, beheaded, and quartered (chopped into four pieces).
 Their remains were often displayed in prominent places across the country, such as London Bridge.
 For reasons of public decency, women convicted of high treason were instead burned at the stake.
The Treason Outlawries (Scotland) Act 1748 (22 Geo.II c.48) was an Act of the Parliament of Great Britain which applied only to Scotland.
 Its long title was "An act to ascertain and establish the method of proceeding to and upon outlawries for high treason, and misprision of high treason, in Scotland."
William Exmew, O.Cart.
, (died Tyburn, 19 June 1535) was an English Catholic priest and Carthusian hermit.
 He died while imprisoned under King Henry VIII and is honored as a martyr by the Catholic Church.
 Exmew and his brother Carthusian martyrs were beatified by Pope Leo XIII on 9 December 1886.
Petty treason or petit treason was an offence under the common law of England which involved the betrayal (including murder) of a superior by a subordinate.
 It differed from the better-known high treason in that high treason can only be committed against the Sovereign.
 In England and Wales, petty treason ceased to be a distinct offence from murder by virtue of the Offences against the Person Act 1828.
 It was abolished in Ireland in 1829.
 It never existed in Scotland.
 It has also been abolished in other common-law countries.

Question: When was the method of execution used on the Carthusian Martyrs of London introduced as the statutory penalty for high treason ?
Answer: 1351