I was kicked out of my lab late in my graduate school career, which destroyed my confidence and obviously delayed my graduation by 2+ years. What's more, my advisor tried to convince me to drop out of graduate school, saying I was just "embarrassing myself", that I just didn't have any ability.
After me, there were many more awful events-- one person (non-student) was fired and rather slandered in an email to the lab; multiple postdocs had their projects pulled out from under them and were forced to start over in another lab, no papers; I know another graduate student there who has been struggling to decide whether to drop out; in all cases this advisor tries to destroy the person's confidence and convince them they are incapable of success.
I tried to talk to the administration a year or so after I got kicked out... just to suggest that such things should not happen without any scrutiny from the uni. I think it was just viewed as sour grapes, and nothing happened. Recently, my (second) PhD advisor suggested in a veiled way that I should try again, and maybe if I got all the other "survivors" together, we would have credibility. I think it would probably be useless and risky for me. But this person should not be in such a position of power over vulnerable junior scientists. Is it morally wrong for me to do nothing? But what could I do? (I think the best action would be for my advisor to organize something but like all advisors, mine 90% only cares about his/her own career).