What to say to prospective students?

Every year prospective students ask about the climate of the department, and if there are any “problematic” professors that they should be aware of. There are. But the department itself can’t/won’t say anything about them so it falls to the graduate students to do so. This has caused a lot of tension in our department because there are a group of students who think that nothing should be said and others who think we have a moral obligation to tell the truth about it. And in the middle of all this are the student(s) who were directly affected by the professors in question. It’s an awful situation.