After filling several situations to learn his business, in 1817 Haughton settled in Dublin, where he became a corn and flour agent, in partnership with his brother William.

He took a leading part in a series of weekly meetings which were held in Dublin in 1840, when so numerous were the social questions discussed that a newspaper editor called the speakers the "Anti-everythingarians".

In association with Daniel O'Connell, of whose character he had a very high opinion, he advocated various plans for the amelioration of the condition of Ireland and the Repeal of the Union, but was always opposed to physical force.

When in July 1846 O'Connell's son John forced a division the increasingly impatient "Young Irelanders" within his father's Repeal Association by tabling resolutions that repudiated political violence under circumstances, Haughton sought to mediate.

[2] In a decision perhaps made easier by Daniel O'Connell's death in May 1847, he ultimately sided with the dissidents: Thomas Meagher argued that the Young Irelanders were not advocating physical force, but might regard a resort to arms as "a no less honourable course" if Repeal could not be carried by moral persuasion.