I've recently become aware of a couple of incidents over the summer involving messy hiring and tenure decisions at various institutions. I won't comment on any specific situation, but a couple of general observations may be in order.
In my experience, things are likely to get messy when faculty are initially hired without widespread departmental and administration support. This is particularly true in small departments and small colleges. A person may turn out to be an inspiring teacher and a perceptive scholar, but if a significant faction among faculty and administrators can't perceive it at the time of the hire, trouble may ensue afterward.
Sometimes this is related to factionalism within the department or between the department and the administration. It is wrong for junior faculty to be put into such conflicts, but it happens with far too much frequency. And there is often little junior faculty can do to improve the situation.
So it is incumbent upon us old folks to ensure that we choose new colleagues who are agreeable to nearly everyone involved, and that we avoid letting disputes with the administration degenerate into ill-will that may imperil our younger colleagues' futures. It is a commonplace at many schools to say that junior hires are always done with an eye to tenure, but sometimes it is the actions of those doing the hiring that have the greatest impact on whether that new hire remains a colleague for life.