Do you believe the Church and the general members have a history of character assassination? From Oliver Cowdery to Emma Smith and lots of more people in between, once they are not part of the fold people start suddenly talking bad things about them, blackening their names. One day they were great, inspiring people but once they left they start saying nasty things about the individual. In other Churches, when a sheep is lost....people go out of their ways to find it and bring it safely home. How is it in our Church? Do we really rescue the sheep or take a gun and put the sheep out of her misery?
With the two names you provided I believe there were many attempts to bring the two back. In the end Emma choose to welcome Members but not go West and Oliver did return, but all on his own. In Oliver's case he claimed misunderstandings - I cover that very deeply in the Oliver Cowdery Thread. With Members in general I think they assassinate people's character all the time if you are out of 'pattern' with Mormon tradition. I have been guilty of that in the past and have chosen to try and put myself in their shoes rather than talk about the person. Often what we want to attack is our own weakness we see in others.
I find that most Mormons, probably including myself, are very judgmental. Since we know Truth, anyone who is not in line with us is bad, if not evil.
One example I can give is that when I was trying to talk to someone about Avraham Gileadi's works on the book of Isaiah, he rejected absolutely everything about Bro. Gileadi because he had been "zapped" or excommunicated. Since he was excommunicated, nothing he ever did was worth anything, although he had been readmitted to the Church by that time.
I also find that gossip runs rampant through the Church. Since gossip is almost always destructive, even if well meaning, the end result is that many people are harmed.
I don't think that there is very much organized character assassination in the Church or the culture, as there is in the political arena. I just think that our pride is such that we are comfortable in touting our superiority over others, especially those who don't believe exactly as we do.