On 28 February 1798, betrayed by the informer
Samuel Turner, Coigly was apprehended in a party with O'Connor, Benjamin Binns, and
John Allen as they were about to embark from
Margate on a
Channel crossing to France. Coilgy had begged O'Connor to come with him to Paris to replace Edward Lewins, the official United Irish envoy, upon whom he had misplaced the suspicion that should identify Turner. Brought before the
Privy Council, Coigly (or O'Coigley as he was commonly referred to in reports) denied under questioning from
William Pitt ever being a member of the Corresponding Society, the Whig Club or "any other of the political societies" in England or to have ever attended their meetings. The arrests and the appearance of the prisoners before the
Privy Council caused great excitement and occasioned, on grounds of conspiracy with France, the arrest, in a raid on
Oliver Bond's house in Dublin, of almost the entire
Leinster directory of the United Irishmen, and a round-up of English radicals extending to Manchester, Leicester and Birmingham. O'Connor impressed the jurors with an appearance on his behalf by
Charles James Fox,
Lord Moria and
Richard Brinsley Sheridan other Whig luminaries, while mounting a defence in which he was reprimanded by the judge for prejudicing the case of the other defendants. In Coigly's coat pocket had been found what proved to be the only admissible evidence of treason, an address from "The Secret Committee of England’" to the Directory of France. While its suggestion of a mass movement primed to welcome
Napoleon, the "hero of Italy", was scarcely credible, it was proof that Coigly's intent was to invite and encourage a French invasion. Coigly refused the offer of his life in return for implicating his fellow defendants who were acquitted. In condemning Coigly, the judge, Justice Buller, derided the defendant's apparent faith in the French government.Could such persons [who had supported Coigly in his mission] hope that they themselves should enjoy liberty, even supposing the conquerors to have enjoyed as free a constitution as any in the world? No, they would become suspected, be despised, and destroyed by them. A celebrated writer (
Montesquieu) very justly observed upon this subject, that a country conquered by a democratic nation always enjoyed less liberty, was more miserable, and more enslaved, than if that country happened to have been conquered by a nation whose government was monarchial. But if there was any illustration of this observation wanting, one had only to look to the conduct of the French at this moment towards Holland, Italy, Switzerland, and every other country they had conquered. He passed the following sentence: "That the prisoner be taken from the bar to prison, and from thence to the place of execution; there to be hanged, but not until he be dead, to be cut down while yet alive, and then to have his heart and bowels taken out and burnt before his face; his head to be severed from his body; and his body to be divided into four quarters." Another account has the government priest, a Father Griffiths (who had helped break the resolve of Irish
mutineers at the Nore), relenting on the day of execution, so that absolution was indeed given. From the scaffold—again according to Madden—Coigly declared that his true and only "crime" in the eyes of those who condemned him was to have "taught the people that no man can serve his God by persecuting other for religious opinions" and to have been "very active in procuring a long address to the king, to put an end to a calamitous and destructive war". Yet Coigly was written out of the general narrative history of 1798. For the centenary of the rebellion, pilgrimages were organised to Maidstone and addressed by members of the
Irish Parliamentary Party, but the events attracted little attention. The assembled attended mass at St Francis Church in Maidstone, where in Coigly's memory they installed three stained glass windows (dedicated to Saints Patrick. Brigid and Francis) and a brass cross inscribed in English and Irish. ==Letter from Prison==