what tense situation occurs at the county jail? How does Scout help her father in this scene?

Atticus confronts a mob lead by Mr. Cunningham. THe mob of men want to take Tom Robinson and carry out their own justice based on racial prejudice. Scout intervenes and speaks to Mr. Cunningham directly. Through her own innocent way, she reminds Mr. Cunningham about how Atticus has helped his family and that his son is a friend of hers. Mr. Cunningham tells the mob to leave.