This movie has a couple of weak points. Unfortunately, such points are so weak that eclipse all the talent in the movie.
First of all, the movie has two clearly differentiated parts that just don't mix well (making a *very* different portrait of detective Jerry Black on each part). Maybe there's some will of creating contrast by concatenation of hope and tragedy in the same movie but, if that was the real will, the movie fails: it gets absurdity rather than contrast.
Secondly, the story is built from a serious promise. The scene where the promise is made is very disappointing because of the weak arguments, circumstances, and acting, for such a serious promise.
Also, as an additional comment, I wish to add that this movie shows a pessimistic view of the experienced old people. If you love stories where young people learn from old people, you may prefer other kind of films rather than this one.
I watched the original version of this movie when I was a child ("Es geschah am hellichten Tag" -- 1958), and I remember it as a very nice experience. I think I enjoyed it a lot, although I don't remember why (I was too young).
I've been very disappointed by this Hollywood remake.