In "To Kill a Mockingbird" why do you think people decided that Boo Radley killed Bob Ewell and that Bob Ewell didn't just fall on the knife?
I know why he would have-but in the novel it doesn't say specifically that Boo killed Bob, so how come people think that Boo did it?
People conclude that Boo Radley killed Bob Ewell because the evidence seems to point in that direction. If you look really closely at the evidence and facts that we DO have (even if we don't have a clear statement of guilt), all of it points logically to Boo Radley. Look in chapter 28, at the actual scuffle that occurred between Bob and the children. It is written through Scout's perspective, and she was blinded by her costume, but through sounds, we know that the man squeezing Scout to death was "suddenly jerked backwards." Scout thinks Jem had done that, but we learn later that Jem's arm was too badly broken to have pulled anyone away. Someone else must have been on the scene, which, we conclude later, was Boo. So Boo jerks Bob off of Scout, and then she hears "scuffling noises" and a man wheezing as if out of breath. He
"leaned heavily against [the tree]. He coughed violently...[then] began moving around, as if searching for something. I hard him groan and pull something heavy along the ground."
After this, Scout hears that same man "walking heavily and unsteadily toward the road." Then, Scout feels around and feels a man on the ground, a belt buckle, and a face.
So, to interpret all of that information, using inference and what we know of Boo, Boo pulled Bob off of Scout, they fought, and then there was silence except for Boo's heavy breathing. Boo was out of shape, used to being indoors, and later on, coughs a lot. So, it must have been Boo coughing and trying to catch his breath. Bob was silent. Then, we hear Boo dragging what must be Jem towards him to pick him up, then walking "heavily" away, which means he had Jem in his arms. Then, Scout feels what must have been Bob on the ground--and his is face up. That is key, because they later concluded (in order to protect both Boo and Jem from accusations of murder), that Bob tripped onto his knife. If he had done that, Bob would have been face down on the ground, not face up. So, someone must have stabbed him.
So, you're right--the novel never specifically says that Boo stabbed Bob, but if you look very closely at the details in chapter 28, and put them together with what we know of Boo and what comes afterwards, then the logical conclusion is that Boo did indeed kill Bob. I hope that those thoughts and explanations cleared things up for you a bit; good luck!
From the description of the struggle, we know Boo was present when Ewell died.
Boo has a history of violence - he stabbed someone with scissors.
Heck Tate worked out that Boo did it, and claimed that Ewell fell on his own knife to protect Boo. He also gave Atticus lots of clues that Boo did it when they argued about it.
"It was mighty dark out there, black as ink. It'd take somebody mighty used to the dark to make a competent witness..." Boo Radley was used to the dark, not Jem or Scout.
"No boy Jem's size with a busted arm could tackle and kill a grown man in pitch dark" - but Boo could.
"God damn it, I'm not thinking of Jem"
"For once you haven't been able to put two and two together"
He's letting Atticus know that he's thinking of someone else rather than Jem, and is frustrated that Atticus hasn't worked out who it is. He can't come out and say it, because then he wouldn't be protecting Boo.
The knife is what convinces Atticus. Heck Tate uses a swithblade knife to demonstrate what happened. Asked where he got it from he answers "a drunk man". Bob Ewell was that drunk man. That was the knife he tried to kill Jem and Scout with.
He was stabbed with a kitchen knife. But Heck Tate knows that it's not Ewell's kitchen knife, so he suggests that Ewell found it in a dump. Because he knows it was Boo Radley's kitchen knife.
Atticus then puts two and two together, and thanks Boo.
it is because people thought that Boo was crazy and he once stabbed his father with a scissor