What did Arthur do to be locked up?
According to Miss Stephanie Crawford--so take we should take this story with a grain of salt--when he was thirty-three years old, Arthur was sitting in the living room cutting clippings from The Maycomb Tribune to paste in his scrapbook when Mr. Radley walked by. Miss Stephanie said that Arthur "drove the scissors into his parent's leg, pulled them out, wiped them on his pants, and resumed his activities" (12). Mrs. Radley panicked and ran into the street screaming that "Arthur was killing them all."
Someone suggested that Arthur be sent to an asylum over the incident, but Mr. Radley wouldn't hear of it. He agreed to have Arthur jailed, but the sheriff wouldn't jail him with African Americans, so Arthur was locked up in the courthouse basement instead.