How do not mess up this Interview Question

I do not have an interview, but I am preparing anyway.

I am asking about nursing school interviews, but this applies to job interviews as well. When you go to the interview, I understand that you are not supposed to speak ill of previous employers (or anybody for that matter) as it will reflect badly on you.

I am looking at interview questions. There is one about describing an ethical decision. Well, I have a really good one but it reflects poorly on the doctor under whom I was working. In fact, I wonder if it is possible to answer this question without the answer reflecting poorly on another. Did you have this question in your interview? How did you handle it? How is this to be handled?

Yes, vagueness would help, but what if in disclosing the scenario, a hint came out and all they had to do was look at your resume and they would know who it was? (If it involves the heart and they see you worked for a cardiologist, they're going to know, you know?)

Thanks!