On October 7, 1878, Mount Vernon newspapers reported that a group of Black men had allegedly robbed a group of white women working as sex workers at a brothel near Mount Vernon, Indiana, in Posey County. Law enforcement identified six suspects: Jim Good, Jeff Hopkins, Ed Warner, William Chambers, John Harris, and Dan Harris Jr. Officers arrested Good, Hopkins, Warner, and Chambers and held them in the county jail to await trial. Before officers could locate the other two suspects, white mobs lynched Dan Harris Jr. and John Harris.
Officers, unaware these lynchings had occurred, went to the home of Dan Harris Sr., the father of Dan Harris Jr., intending to arrest his son. Harris Sr. told them his son had already been lynched the previous day. Officers then accused Harris Sr. of harboring his son and attempted to force entry into the home. Harris Sr. shot Deputy Sheriff Cyrus Thomas with a shotgun; the city marshal returned fire, wounding Harris Sr. before taking him into custody. Deputy Sheriff Thomas died at the scene. Harris Sr. was placed in the same jail holding Good, Hopkins, Warner, and Chambers.
As news of the arrests and the deputy's death spread, a mob gathered outside the jail. Officers initially refused to allow the crowd inside despite escalating tension. Rumors that the governor had summoned the state militia drew roughly 200 armed white men to the nearby train station, where they blocked militiamen from disembarking and moved a cannon from the courthouse lawn to the depot. The militia never arrived, and the crowd dispersed by around 2 p.m. on October 11, 1878.
The mob reconvened that evening, and around 100 masked men approached the jail after dark. Over roughly 45 minutes, using crowbars, chisels, and a sledgehammer, they broke through the cell's iron door. Harris Sr., held separately and in poor condition from his untreated gunshot wounds, was dismembered by the mob, with body parts taken as souvenirs. The mob then removed Good, Hopkins, Warner, and Chambers from the jail with bound hands and ropes around their necks. The men attempted to assert their innocence and account for their whereabouts on the night of the alleged robbery, but were hanged from a tree on the nearby courthouse lawn. Their bodies remained hanging into the next day, viewed by thousands of people from surrounding counties.
Following the lynchings, a Georgia newspaper, The Augusta Chronicle, used the event to criticize Northern condemnation of Southern lynch law. The Equal Justice Initiative has documented 18 victims of racial terror lynching in Indiana overall, and Ed Warner, Jeff Hopkins, Jim Good, William Chambers, and Dan Harris Sr. are memorialized at the organization's National Memorial for Peace and Justice on the Indiana marker. In October 2022, Posey County dedicated a historical marker and granite bench outside the Posey County Courthouse commemorating the victims.