According to Miss Stephanie Crawford, Boo stabbed his father in the leg with a pair of scissors while he was clipping items from the Maycomb Tribune.
“Boo was sitting in the livingroom cutting some items from The Maycomb Tribune to paste in his scrapbook. His father entered the room. As Mr. Radley passed by, Boo drove the scissors into his parent’s leg, pulled them out, wiped them on his pants, and resumed his activities.” (1.13)
According to Miss Stephanie, Boo’s parents refused to put him in an asylum, and Boo wasn’t charged with anything following the stabbing. As the story goes, Boo was locked in the courthouse basement because the sheriff did not have the heart to put him in the jail alongside Negroes. Miss Stephanie is Maycomb’s notorious gossip and fuels the children’s imaginations with stories of Arthur ‘Boo’ Radley. During the summer, Jem, Scout, and Dill subscribe to the stories and rumors of Boo Radley that they hear throughout the town, and eventually make up a game where they play/act Boo’s life story. They even recreate the scene in which Boo stabs Mr. Radley using a pair of scissors that they took from the sewing drawer when Calpurnia wasn’t looking.
According to the gossipmonger Miss Stephanie Crawford, who lives across the street from the Finches, Boo Radley stuck a pair of scissors into his father's leg as the man passed by him while Boo sat on the floor, cutting articles from The Maycomb Tribune. Boo then pulled out the scissors, wiped the blood on his pants, and calmly returned to what he was doing.
This apparent act of retaliation by Boo Radley has as its cause the permanent confinement to the house which his father has forced upon him. Since his arrest as a teenager, Arthur Radley has been an inmate of what Miss Maudie calls "a sad house" (Ch. 5).
Rather than have his son go to the state industrial school after his arrest for disturbing the peace, an arrest which Mr. Radley considered a disgrace, Mr. Radley allowed his son to be imprisoned in the basement of the courthouse. Finally, Boo was released to his father, who has had Boo cloistered for many years in their house. According to Miss Stephanie, after Boo was there for such a long time, "some of the town council told Mr. Radley that if he didn't take Boo back, Boo would die of mold from the damp."
Now Boo is a prisoner in his own home.