Atticus shoots and kills the rabid dog in Chapter 10. At the beginning of the chapter, Jem and Scout complain about their father's age and uninteresting occupation. Jem wishes that Atticus would participate in the touch football game between the Methodists and Baptists, and Scout laments that all her father does is sit in the living room and read. Even though Jem and Scout love Atticus, they find his life rather boring and mundane.

Everything changes one Saturday when Jem and Scout come across a rabid dog named Tim Johnson staggering down the main street of town. Once Calpurnia investigates and concludes that Tim Johnson is rabid, she immediately calls Atticus at his office. Atticus arrives on the scene with Sheriff Tate, who gives him the rifle and instructs Atticus to shoot the rabid dog.

Sheriff Tate knows that Atticus is an expert marksman and trusts him to take the difficult shot. Atticus reluctantly takes the rifle and kills Tim Johnson in one shot. Jem and Scout are in awe of Atticus and astonished by his impressive marksmanship abilities. After Atticus shoots and kills the rabid dog, Miss Maudie calls him by his former nickname "One-Shot Finch" and the children wonder why he never spoke about his shooting skills. Miss Maudie responds by telling Jem and Scout, "People in their right minds never take pride in their talents."

The incident of Atticus shooting a rabid dog named Tim Johnson takes place in chapter 10.

When the dog strays into the neighborhood, Jem spots him, and he tells Calpurnia to come and have a look. Calpurnia initially suspects that Jem is “telling [her] a story.” Once Calpurnia sees the dog “gone lopsided,” she reacts immediately, ushering the children inside to safety. She then gets on the phone, first reaching Atticus at his office, then ensuring that other neighbors are aware that “a mad dog’s comin’.” Calpurnia orders the children to stay in the house, then heads to the Radley place to try to ensure that everyone is aware of the danger.

The Sheriff, Heck Tate, who arrives at the Finch household with Atticus, confirms that the dog is rabid. With Tate unwilling to take the necessary shot to end the animal’s life, the responsibility falls to Atticus.

Jem and Scout, who have been feeling embarrassed about their old, non-football-playing, glasses-wearing father, are impressed to learn that he once had a reputation for being a deadly accurate shooter. Once Atticus has shot Tim Johnson, he warns Jem that the danger is not over and that he must not go anywhere near the dog.

In Chapter 10 of Harper Lee's To Kill a Mockingbird, Atticus shoots a rabid dog. The background of this incident is actually the main theme of the novel. Before a school trip, Atticus tells his two children that to kill a mockingbird is a sin. The mockingbird, a beautiful and innocent creature, would have no agency over its own fate. The bird is a metaphor for Tom Robinson, the innocent black man whom Atticus defends in court. The conversation is in the context of Jem and Scout's belief that their father is a weak and feeble man. He is older than the other parents, wear eyeglasses, and has the demeanor of a kind and academic lawyer (which he is). He refuses to teach them how to shoot their air rifles, and instead talks of non-violence and peace. Jem and Scout wish he were "cooler," to use a modern colloquialism. 

The shooting of the rabid dog is one of the many surprise moments in Lee's novel. When Calpurnia sees the dog, she calls both Atticus and Mr. Heck Tate, the sheriff of Maycomb county. She knows about Atticus's secret talent. The sheriff and Atticus wait on the abandoned street for the rabid dog, which is a suspenseful confrontation, especially for Scout and Jem. The sheriff hands Atticus his gun to kill the dog. It turns out that Sheriff Heck Tate knew all along that Atticus Finch was the better shot, and acted accordingly. Atticus was once known was "One-Shot Finch," but he has long since given up shooting. He hides this from people, including his children, because he values peace over this talent, which is based in violence and aggression. S

Scout and Jem are awed by this new version of their barrister father. Scout desperately wishes to brag to all her peers about Atticus "One-Shot" Finch, but Jem forbids her. This moment indicates how Jem is maturing. Scout, still very young and rambunctious, can only think of the shooting of the rabid dog as an exciting event. But Jem, who is growing up, begins to understand why Atticus hides the things he does and why he is the way he is. 

The scene shows Atticus in a different light to the reader as well. The reader already knows that he is a good human being and a good father. He cares for his children and their moral and intellectual growth. This chapter adds a new layer of badassery to the figure of Atticus Finch. 

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Atticus is called in to deal with the mad dog, Tim Johnson, in Chapter 10 of To Kill a Mockingbird. Sheriff Heck Tate decides to turn the job of killing the dog over to Atticus, much to the amazement of Jem and Scout, who are watching from the Finch's front porch. Unknown to them, Atticus was once the finest marksman in the county--known as "One-Shot Finch." Sheriff Tate knew that Atticus was the better shot--rusty or not. The children wondered why Atticus had never told them about this hidden talent, but Miss Maudie explained that it was just his humble nature.

In what chapter of Harper Lee's To Kill a Mockingbird does Atticus shoot a rabid dog?

By Chapter 10 of Harper Lee's To Kill a Mockingbird, Scout and Jem are starting to feel disgruntled by their father's persistent absence due to his devoted work on the Tom Robinson case. Scout also blames Atticus's absence on old age, saying, "Atticus was feeble: he was nearly fifty" (Ch. 10). As a result of Atticus's increased absence, the Finches' cook Calpurnia, Cal for short, spends even more time taking over as a surrogate parent. One way in which she acts as a surrogate parent in Chapter 10 is by protecting the children from a rabid dog.

One Saturday, Scout and Jem went hunting with their air-rifles in search of a rabbit or squirrel to shoot at when Jem noticed a dog named "old Tim Johnson," who belonged to Mr. Harry Johnson, driver of the "Mobile bus," coming down the street. Whatever way the dog was behaving worried Jem enough to decide they should go home and inform Cal. When they do, though Cal protests at being asked to come out and look at a dog, she finally does, and they all observe that the dog "walked erratically, as if his right legs were shorter than his left legs." Calpurnia then ran the children inside the home, "shut the wood door behind [them]," and phoned Mr. Finch, who tells her to warn everyone on the street that a "mad dog's comin'," meaning a rabid dog. Soon Atticus arrives with Sheriff Heck Tate, who has a riffle but insists Atticus shoot the dog with the rifle because Heck knows he's not nearly as good a shooter as Atticus.