Hoar was prevented from undertaking his appointed tasks by resolutions of the legislature and efforts of the governor of South Carolina, and was escorted back onto a ship by Charleston citizens fearing mob violence against the agent from Massachusetts.

South Carolina agents would arrest free African American seamen from Massachusetts, members of the crew aboard ships that arrived at South Carolina sea ports; if the arrestee or the captain of the ship failed to pay fines for the criminal entry into the state, the arrestee would be sold into slavery to pay the fines.

In 1844 the Massachusetts legislature authorized the governor to appoint a Commissioner to reside in Charleston, South Carolina and New Orleans, Louisiana, to collect information as to the number from Massachusetts citizens unlawfully seized in those cities, and to prosecute some of the suits before higher courts for the purpose of testing the constitutionality of the laws under which the forcible seizures were being made.

That his excellency, the governor, be directed to expel from our territory the said agent, after due notice to depart; and that the legislature will sustain the executive authority in any measures that may be adopted for the purpose aforesaid.The effective result was that Hoar was prevented from appearing before that state's courts to test the law.

Local leading citizens secretly escorted the Hoars out of their hotel, to a ship, in advance of feared mob violence.

She prohibits, not only by lower mobs, but by her legislature, the residence of a free white citizen of Massachusetts within the limits of South Carolina whenever she thinks his presence there inconsistent with her policy.

[4] In 1854, he chaired a committee which issued an announcement, summoning leading anti-slavery politicians and citizens to a meeting at the American House in Boston (July 7, 1854), to discuss the potential formation of a new party and to organize a state convention.

Anger over the Kansas-Nebraska Act, and the issue of slavery in Federal territories were motivating factors leading to the subsequent convention in Worcester.