When Sheriff Tate and the other men met in the Finch's front yard, Scout recognized that something important was going on.
In Maycomb, grown men stood outside in the front yard for only two reasons: death and politics. I wondered who had died.
But no one had died. The men were meeting to discuss Tom Robinson's move to the county jail, and the problems that might arise from troublemakers who would prefer to not see Tom go to trial at all. The men probably decided to meet outside because in the Deep South, important matters were often not discussed inside the house--and certainly not in front of women or children. Alexandra, Jem and Scout were all at home, and both Sheriff Tate and Atticus probably realized immediately that the front yard was the best spot for their conversation. The yard was still not far enough away from the prying eyes and ears of Jem and Scout, however.
At the beginning of Chapter 15, Sheriff Tate, Link Deas, Dr. Reynolds, Mr. Avery, and a few other citizens meet in Atticus' front yard to discuss moving Tom Robinson and the risks posed by the Old Sarum bunch, who will probably try to lynch Tom. Scout and Jem watch Atticus talk to the men from inside the house and try to figure out what they are discussing. Scout comments,
"In Maycomb, grown men stood outside in the front yard for two reasons: death and politics" (Lee 193).
From this statement, one can infer that in the South, the small town communities are relatively close-knit. Death and politics are serious topics of discussion and the fact that neighbors would travel to each other's homes to discuss such things suggests that citizens are close with one another.
However, the men of Maycomb do not discuss either topic when they visit the Finch home. Their visit is a reminder that Atticus has supporters in the town who are genuinely concerned about his well-being and wish to maintain order.
"In Mayfair, grown men stood outside in the front yard for only two reasons: death and politics."
You can find this quote in Chapter 15.