In Chapter Seventeen, Atticus demonstrates his excellent skills as a lawyer. Atticus treats both the sheriff and Ewell with respect, and carefully asks questions that poke holes in the Ewells' claims. For instance, he first determined exactly what injuries Mayella suffered, and then manipulates Ewell into revealing that he is left-handed, and that a left-handed man most likely beat Mayella, causing bruising on the right side of her face.
Atticus is as much the gentleman in the courtroom, as he is in his everyday life.
He moved leisurely, and had turned so that he was in full view of the jury. He unscrewed the fountain-pen cap and placed it gently on his table. He shook the pen a little, then handed it with the envelope to the witness. “Would you write your name for us?” he asked. “Clearly now, so the jury can see you do it.”