William Sampson was one of many non-Catholics who were disturbed by the level of discrimination and violence against members of the Catholic faith. Anticipating an insurrection in March 1798, as a lawyer, Sampson defended United Irishmen for anti-British actions and was imprisoned, disbarred, and banished from Ireland without trial for his courtroom and literary activities.

After eight years of political exile in Europe, Sampson was finally allowed to enter the United State. He arrived in New York City on 4 July 1806, where he continued to promote the United Irish principles of political reform and religious toleration as a distinguished attorney and legal reformer. He set up a business publishing detailed accounts of the court proceedings in cases with popular appeal. His most lasting impact on American judicial law was when he won a judgment accepting the confidentiality of the confessional. He published his Memoirs in 1807, and a work on the Catholic Question in America in 1813.

The opening lines of Sampsons Memoirs read:

“At length, I take up my pen… to give you the history of my extraordinary persecution. From it you may form a judgment of that system of government which drove the unhappy people of Ireland to revolt. But, to judge rightly, you should also be aware, that of many thousand such cases, mine is one of– the most mild.”

Sampson also remarks in his Memoirs that he had had a promising career and future ahead of him when he was called to the bar in 1792, yet six years later he had been branded a rebel and a traitor. Sampson explains his transformation from patriot to rebel thus:

Being of the favoured cast, and far from having any personal griefs, the road to advancement on the contrary very open to me, I could have no motive but that of compassion for my country. I was never inclined to political contention; and it required strong conviction to move me to sedition…. The griefs of Irishmen are undeniable.

William Sampson died in New York City on 28 December 1835, aged 72. His daughter, Catherine, married Theobald Wolfe Tone’s son, William Theobald Wolfe Tone.