On 6 May 1882, the most senior Irish civil servant, the Permanent Undersecretary, Thomas Henry Burke and the newly appointed Chief Secretary for Ireland, Lord Frederick Cavendish – who was also the nephew of Prime Minister William Ewart Gladstone – were killed as they walked through Phoenix Park in Dublin by a man who stabbed them both with hospital scalpels.
A more radical splinter group, the Invincibles, planned to execute Thomas Burke, a Catholic who collaborated with British rule by helping to administer it from Dublin Castle.
The new Chief Secretary of Ireland, Lord Frederick Cavendish, was not an intended victim but happened to be out walking with Burke at the time of the attack.
The hunt for the perpetrators was led by the Royal Irish Constabulary's Superintendent John Mallon, who arrested a number of suspects.
[4] Following Carey's testimony, five men were hanged at Kilmainham Jail for the killings between May and June 1883: Joe Brady, Daniel Curley, Tim Kelly, Thomas Caffrey and Michael Fagan.
Carey maintained his assumed identity for most of the voyage, but later let his guard down, provoking a row in Cape Town and displaying his revolver.
O'Donnell was represented by Sir Charles Russell, MP, afterward Lord Chief Justice of England, Alexander M. Sullivan, Messr.
As there was no proof that O'Donnell had set upon his voyage with the intention to murder Carey, the case was made that the informer had been recognised by a fellow passenger on the Kinfauns Castle, Robert Thomas Cubbit, who testified that he had guessed "Power"'s real identity when he was shown a copy of the Dublin Weekly Freeman with Carey's portrait in it, along with a description of his testimony against his fellow Invincibles.
Russell argued that to be surely because of poor light and that Carey most certainly had a gun on his person at all time for his own protection, especially since his identity had been discovered.
After deliberating for only two hours, the jury returned a verdict of guilty of wilful murder at 9 p.m. on 1 December 1883, upon which O'Donnell was sentenced by the judge to death by hanging.
"[9] The President of the United States at the time, Chester A. Arthur, officially petitioned on behalf of O'Donnell once it was determined he had acquired American citizenship.
[12][13] O'Donnell's links to the Mollies and his revenge against Carey are believed to have inspired Sir Arthur Conan Doyle's book, The Valley of Fear.
Wreaths of immortelles were placed on the coffin which bore the inscription Sacred to the memory of Patrick O'Donnell, executed at London 17 December 1883.
The committee consisted of 21 local Fianna Fáil cumann members who held fund-raising events to finance the building of the cross.
Several pleas were made for his life by Victor Hugo[16] According to the Freeman's Journal and Daily Commercial Advertiser: "President Chester A. Arthur received a deputation urging him to press for clemency consisting of congressmen Cox and Robinson, New York; Mirrosn, [sic] Springer, and Sinertz, Illinois; Lefevre and Foran, Ohio; Murphy, Iowa; Mabury, William Lamb, Indiana; M'Adoo, New Jersey; Collins, Massachusetts, and O'Neill and Burns, Missouri."
[17] A novel about Patrick O'Donnell has been published with the premise that upon learning of the interventions on his behalf by Victor Hugo, O’Donnell is purported to have written a series of 26 letters to the famous author and humanitarian; letters which never reached their intended recipient but were apparently discovered in 2016 and published in 'The Execution, Life and Times of Patrick O'Donnell'.
[18] In 2022, a newly discovered manuscript of a novel by the important Irish-language writer Séamus Ó Grianna about O'Donnell was published under the title Báire na Fola.