And not to defend Rice (even though some imbecile will probably think that's what I'm doing), we don't know if Rice hit her hard enough to knock her unconscious, let alone to kill her. We simply know he hit her hard enough to knock her down. The elevator handle may be responsible for her going unconscious. (Of course Rice is responsible for all of that, I'm only commenting on how hard he hit her, as that seems to be a relevant distinction for you ... it's not for me.)

Again, I think you are being very generous with Peterson to assume his intentions were benign. It seems to me that he lost his cool as a parent (that alone is understandable), and took his anger/frustration out of his son. But we can agree to disagree.