How to avoid training a harasser As a postdoc and junior faculty member I was involved in mentoring and training a PhD student who went on to a faculty position. I have now heard that the person I trained has been investigated and suspended by their university for harassing students.

Looking back I cannot think of anything that I did whilst mentoring and training to encourage this behaviour. However, neither can I think of anything I did to discourage it. I also can't immediately think of what I'm doing now, with current graduate students, to discourage this behaviour in the future.

What are good strategies for faculty mentoring and supervising students to reduce the chance of training a future harasser?

EDIT: Thanks for the answers so far. However, none have added specific strategies that I feel I could act on. As an example of what I'm looking for:

When discussing conferences that students may attend, I would talk with them about


How good/useful the list of invited speakers and sessions looks;
What the expected participants are like, and whether they'd be useful for their future network (is this a good/useful community to engage with);
Whether it fits within their travel budget;
What opportunities there are to present talks or posters;
How useful associated training activities may be;
Whether they'd be able to combine the conference with visits to nearby groups that may be useful;
How it fits around other commitments in their calendar.


I am now thinking of extending this to include


Discussions of the meeting's Code of Conduct: why having one is good, violating it is bad, and my expectation that they should follow a suitable Code of Conduct even if the meeting doesn't officially have one;
Noting the balance and diversity of speakers (I've been doing this more anyway, but making it more explicit that this is good, and that students should interact professionally with all participants), and discussing in problematic cases if lack of diversity at a meeting indicates other problems in the community around that meeting;
Emphasizing that students should pay attention when meeting participants talk about "personalities" in the field; that this information should be respected, listened to, and considered carefully; and that they should think about how to avoid causing the sort of problems that others discuss.


I need to consider the points that @Fomite and @D. Salo bring up, particularly how to implement a group Code of Conduct that works with, rather than at cross-purposes to, existing university policies. I'm looking for detailed ideas that I can use in other frequent interactions with students.

Finally, I refuse to believe that there's little more that can be done other than setting a good example. We continually demand improvement in our research and our teaching: in these parts of our professional lives we know that concrete, incremental steps show real gains. Building and training a community of professional researchers that act professionally in personal interactions is also part of our jobs. I don't expect perfection, but I'm extremely angry that this has happened, so I do expect improvement of myself, and I think the field should too.
This might prove futile, in my eyes. If you mandate something like sensitivity training, say, you will teach those naturally well-behaved little, and those who carry the germ of future mis-behavior to hide it. If you advise students from different cultures, on the other hand, it might help them to learn what is appropriate in yours. So in that case it might be a good idea as some mis-behavior results merely from different cultural norms (a kind and friendly Asian co-student shared a racist joke via email with all my school - because he didn't recognize it for what it was). For anything happening while working with you, you should make it explicitly known that you encourage your students and postdocs to talk to you should one of them feel that they were treated inappropriately by another; that you always have an open door. 

Marcus Aurelius was a philosopher emperor devoted to service and tolerance; his son Commodus arguably the most wicked Roman emperor in the history of the Roman Empire. You try to set a good example, but that is probably all you can do. Don't beat yourself up over what happened.