Look, I don't excuse murder, even by wronged wives or husbands. I just say it's one of the reasons to steer clear of adulterous activities - because violence can be one of the side effects. This Dr. Harris didn't think about that, apparently. That doesn't mean he deserved to be murdered(he didn't) - or that his wife should get off (she shouldn't)- - - but it does mean that he was being more than immoral, he was being stupid.
I learned this lesson as a kid. One of the family members was an emergency room doctor. He remarked how many if not most of the violence victims brought had been involved in marital disputes where somebody'd been jealous of the other. We deny the potentially fiery consequences of jealousy and betrayal at our peril. That's not a "moralistic" statement, it's just an observation about human nature.