Mr. Harvey (Susie Salmon's killer) dies on page 327 of the very last chapter called "Bones" (the only chapter with a verbal instead of a numerical name); however, it is not the fact that he dies that is important, it is HOW he dies that is important. You see, Susie Salmon had numerous conversations with her sister while she was alive about an icicle being the absolute perfect murder weapon: a weapon that leaves no evidence whatsoever. This is, in fact, how Mr. Harvey dies. All of this happens after Mr. Harvey tries to "engage in conversation" (obviously with ulterior motives) with a teen outside of a diner. Here is what it says in the text:
It was then that I noticed them, hanging above their heads in a long and plentiful row. Icicles.
The girl put out her cigarette on the heel of her shoe and turned to go.
"Creep," she said, and walked fast.
A moment later, the icicle fell. The heavy coldness of it threw him off balance just enough for him to stumble and pitch forward. it would be weeks before the snow in the ravine melted enough to uncover him. (327)
Although there is absolutely no evidence in the text that Susie Salmon, in the confines of her afterlife, is the one who actually used the icicle to kill Mr. Harvey, it is pertinent that she is watching Mr. Harvey at that moment and does notice the icicles. It only takes one more moment for the icicle to fall and disturb Harvey's balance.