Ethos, pathos, and logos are all forms of rhetoric which make an argument stronger. This is especially important as both lawyers are presenting evidence and questioning witnesses in the trial of Tom Robinson.

Ethos is an appeal to credibility and trust. In Tom's testimony, Atticus shows that he visited Mayella's place before, helping with small jobs she needed and never asking for any money in return. This shows that Mayella trusted Tom. Atticus also shows that Tom is employed by Link Deas, a white man in town who stands up to defend Tom's honor during the trial by telling everyone that "that boy's worked for me eight years an' I ain't had a speck o' trouble outa him." Atticus builds Tom's character to show his credibility as a witness.

Pathos is an appeal to the emotions of the audience. Atticus relies heavily on this technique in his interview of Mayella. By showing her living conditions, Atticus also shows why she would lie and accuse Tom of such horrific crimes. Her mother has died, she's been left in charge of all her younger siblings, she is functionally illiterate, and she doesn't understand basic human respect when Atticus extends that to her. When Atticus presses her in her testimony about how she could have possibly received the injuries from Tom that she's accused him of, Atticus is visibly upset by having to bring her entire situation to light in front of the courtroom. This emotional appeal to the jury shows that though Mayella lives in fear of her drunken and abusive father, and her situation is painful to realize in its entirety, Tom Robinson is not to blame and only tried to help a desperate girl.

Logos is an appeal to logic. When Atticus proves that Bob Ewell is left-handed, consistent with the injuries Mayella has received, while Tom Robinson's left arm has no functioning capacity, he is using logic to show that Bob is the true criminal, not Tom.