In Harper Lee's To Kill a Mockingbird, the first point Atticus makes is that even after this alleged crime of rape, no one called a doctor. This is a serious breach in the prosecution's ability to charge Tom Robinson with sexual assault if a doctor could not confirm it with an examination. It also seems odd that no one cared enough for Mayella to call a doctor to simply see if she was all right, regardless of the ramifications affecting the court case.
"Did you call a doctor, Sheriff? Did anybody call a doctor?" asked Atticus.
"No, sir," said Mr. Tate.
"Didn't call a doctor?"
"No sir," repeated Mr. Tate.
"Why not?" There was an edge to Atticus' voice.
"Well I can tell you why I didn't. It wasn't necessary, Mr. Finch. She was mighty banged up. Something sho' happened, it was obvious."
"But you didn't call a doctor? While you were there did anyone send for one, fetch one, carry her to one?"
Heck Tate continues, pointing out that she was beaten badly, and that "she had a black eye comin'."
This point sticks in Atticus' mind, and this is the second point Atticus makes, without explaining—at this time—why it's important. He asks Heck to describe which eye was blackened. Atticus wants to clarify exactly which eye it was, based on the way Heck was facing, or based upon which side of the face the eye was on: Tate thinks about it and then affirms that it was her right eye. Looking at Tom, Heck remembers something as a thought occurs to him; Atticus asks Heck to repeat himself, as something (the same thing) has occurred to him, too.
"Sheriff, please repeat what you said."
"It was her right eye, I said."
"No…" Atticus walked to the court reporter's desk and bent down to the furiously scribbling hand. It stopped, flipped back the shorthand pad, and the court reporter said, "'Mr. Finch. I remember now she was bunged up on that side of the face.'"
Atticus looked up at Mr. Tate. "Which side again, Heck?"
"The right side, Mr. Finch…"
Atticus is intent on reminding the jury that no doctor was called to confirm the alleged rape, and that Mayella had been struck on the right side of the face. This will become a central point of consideration as the court case advances.
Mayella was beaten from her right side so a man who is left handed must have done it.