Verysadbloke’s comment > Likes and Comments

No, that doesn't work. All of the inconsistencies--this knife, that knife, on his back, not on his back--are created by Heck to shield Boo from prosecution. The fact that Heck knows Boo doesn't mean anything except that he, as sheriff, has been in the Radley house before (which obviously he has, because they are people, and not terrifying monsters, something that Scout learns for herself in the end, when she says hi to Boo and walks him home). Heck will have had reason to interact with the Radleys.

Heck is a lawman, like Atticus. He doesn't sneak out in the night to kill people. His idea of justice has a little bit of a grey area, which is why he cooks up the story, but not so much that he's going to break a law (both a judicial and moral one) just because.

Also, nobody believes that Jem did it, except for Atticus briefly. Even in Scout's confusing recounting of the situation, you can tell that Jem is knocked unconscious before Bob falls dead.

The possibility of Heck killing Bob is something that I never considered. I read the book years ago and have seen the movie several times. I am going to re-read the book with this outcome in mind to determine if I this may be so.