Brady is a member of the Irish National Invincibles, usually known as the Invincibles, a splinter group of the Irish Republican Brotherhood. This group of assassins is active in Dublin between late 1881 and 1883, with an intent to kill the authorities in Dublin Castle.
After numerous attempts on his life, Chief Secretary for Ireland William Edward “Buckshot” Forster resigns in protest of the Kilmainham Treaty. The Invincibles settle on a plan to kill the Permanent Under Secretary Thomas Henry Burke at the Irish Office. The newly installed Chief Secretary for Ireland, Lord Frederick Cavendish, is walking in Phoenix Park with Burke on Saturday, May 6, 1882, the day of his arrival in Ireland, when the assassins strike.
The first assassination in the park is committed by Brady, who attacks Burke with a 12-inch knife, followed in short order by Tim Kelly, who knifes Cavendish. Both men use surgical knives. The British press expresses outrage and demands that the “Phoenix Park Murderers” be brought to justice.
A large number of suspects are arrested. By playing one suspect against another, Superintendent Mallon of G Division of the Dublin Metropolitan Police gets several of them to reveal what they know. The Invincibles’ leader, James Carey, and Michael Kavanagh agree to testify against the others. Carey is ultimately given passage to South Africa but is shot on board the Melrose Castle by Patrick O’Donnell. O’Donnell is brought back to England and hanged in December 1883.
Brady, Michael Fagan, Thomas Caffrey, Dan Curley and Tim Kelly are hanged by William Marwood in Kilmainham Gaol in Dublin beginning with Brady’s execution on May 14 and and continuing until June 4. Others are sentenced to long prison terms.
No member of the founding executive, however, is ever brought to trial by the British government. John Walsh, Patrick Egan, John Sheridan, Frank Byrne, and Patrick Tynan are welcomed in the United States, where sentiment toward the murders is less severe, although not celebratory.
Brady by all accounts was a mountain of a man. The Times writes following his execution: “He was brought up as a stonemason of herculean strength, his occupation developing the muscular power of his arms, which told with such terrible effect when he drove the knives into the bodies of Lord Cavendish and his secretary T. H. Burke.”
Kilmainham Gaol contains the graves of the Invincibles convicted and executed for the Phoenix park stabbings.