system
Given the following post, respond as if you're commenting on Reddit:
human
One of my doctoral students (also a co-author) is about to be removed from the program. What do?

This is my throwaway account, obviously. Here's the story: 

I'm on his committee, and we have collaborated for the last few years on a number of projects. We've published together, we've run professional development events together, and we've co-presented papers at the major conferences in our field. I'm friends outside of the university with him, his wife, and his children. We currently have several active research threads going, and this student just defended his dissertation proposal and it was fabulous. 

And then he sexually harassed multiple undergraduates, all with a solid paper trail. He was their professor (as part of his GA work) at the time. 

He was immediately removed from all teaching functions and from all of his other graduate assistant duties, and next up is the hearing as to whether he may continue to pursue his doctorate in our program. It's all very confidential and only a few people know about it-- but those who DO know are horrified, outraged, and deeply saddened on behalf of the young women. 

So here's where it gets mixed up for me: I'm pre-tenure, and working hard to thicken my portfolio of publications and completed research projects. I currently have open projects with him as co-author, and I am horribly torn about how to proceed. One of the things is nearly done--- but now I have concerns about my name being associated with his. And he HAS contributed a great deal to this research, so it would feel weird to somehow trim him out of this. I have other collaborators who can step in, but... we've already put in so much foundational stuff that it would seem dishonest and unethical to remove his name from this work. 

Does anyone else have experience with something like this? I feel like I'm floundering. 

TL; DR: How to proceed when a collaborator has violated some key ethical norms?
gpt
Give credit where credit is due, but cut ties and move away. It would be unethical to not credit the work done, however it would be dangerous to continue the association from this point forward.
What he did is not your fault. It's not like you knew it was happening and continued to work without saying anything for personal benefit. It would also be silly to throw away that much work for someone's wrong doing, unless the wrong doing directly impacted participants in the study. 

I have also known others to cut authorship, but maintain a section recognizing important contributions from.