In Chapter 15 of To Kill a Mockingbird, a mob, known as the Old Sarum bunch, attempt to harm Tom Robinson while he is sitting in his jail cell awaiting trial. The book does not explicitly mention the mob's intention, but one can infer that the mob possibly intended to lynch Tom Robinson. The setting of the novel takes place during the early 1930's in Alabama. During this time period, lynchings were a commonplace event throughout the South. According to the Washington Post, "Researchers said they determined that 3,959 black people were killed in “racial terror lynchings” in a dozen Southern states between 1877 and 1950."

Earlier in the chapter, Jem references the Ku Klux Klan, which was notorious for racially motivated crimes. Atticus tells them that they were more of a political organization in Maycomb and left town in the 1920's. This reflection of a historically violent group synonymous with lynchings hints at the mob's intentions. Also, the fact that the mob went to the trouble of misleading Sheriff Tate on a fake "snipe hunt" points towards the seriousness of the ordeal. In addition, the mob planned to harm Tom Robinson on a Sunday, which was out of the ordinary because they typically go to church on Sunday and don't drink. The attack on Tom Robinson is considered a "special occasion."

Given the historical background of racially motivated crimes in the deep South, one can infer that the Old Sarum bunch was most likely going to lynch Tom Robinson. If the Finch children did not show up, Atticus would have had trouble stopping the drunk men from imposing their will on him and Tom Robinson.