The object of the Invincibles was to remove all "tyrants" from the country, and several attempts, but without success, were made to assassinate Earl Cowper and W. E. Forster.
[citation needed] For eight months no clue could be found to the perpetrators of the act; but on 13 January 1883, Carey was arrested and, with 16 other people, charged with a conspiracy to murder public officials.
When arrested, he was erecting a mortuary chapel in the South Dublin Union, and the work was then carried on by his brother Peter Carey.
On 13 February, Carey turned queen's evidence and betrayed the complete details of the Invincibles and of the killers in the Phoenix Park.
[citation needed] With his life in great danger, he was secretly, with his wife and family, put on board the Kinfauns Castle, bound for the Cape, and sailed on 6 July under the name of Power.