Link Deas refers to the Cunninghams as the "Old Sarum bunch" because of the area of the county from which they hail. They are a large family who has a reputation for causing trouble when they get drunk together. Atticus asks Deas, ". . . you're not scared of that crowd, are you?" Deas responds with, ". . . know how they do when they get shinnied up" (145). This suggests that there is no evidence that the Cunninghams will cause trouble before the Tom Robinson case, but if they all get drunk together, and get talking about the case, they might.
As a precaution, Atticus takes a light on the end of an extension cord so he can read by the jail the night before the trial. Sure enough, the Cunninghams show up. Since the story is written from Scout's perspective, it is interesting to note that she does not mention seeing a rope, lighted torches, or even guns in the hands of the mob. Those things would probably be the first things a little girl would notice. The point is, even though the Cunninghams seem to be at the jail that night to lynch Tom, they also don't seem very riled up, or as prepared as a serious mob would be. In addition, this might also show that the Cunninghams aren't mean enough to actually carry something like that out. Had they been hell-bent on lynching Tom, no child, attorney, or jail cell would have stopped them. Therefore, it seems as if the Cunninghams weren't very committed their plan when they showed up. Plus, they easily stopped to talk and then listened to a child when Scout spoke. It doesn't seem like they were as organized as they may have intended. When Scout spoke to Mr. Cunningham, he did not stop her, either, as in the following example:
"I began to feel sweat gathering at the edges of my hair; I could stand anything but a bunch of people looking at me. They were quite still. . . I looked around and up at Mr. Cunningham, whose face was equally impassive. Then he did a peculiar thing. He squatted down and took me by both shoulders.
'I'll tell him you said hey, little lady,' he said. Then he straightened up and waved a big paw. 'Let's clear out,' he called. 'Let's get going, boys'"(154).
Whether the Cunninghams would have followed through with the lynching is unknown, but lucky for Scout that Mr. Walter Cunningham seemed to be in charge and easily swayed by his fatherly senses.