[padseeker]

When I get interrupted before things get too far I immediately say "Can I finish what I was saying I was not done". This has been very effective.

And under circumstances where your coworker does not answer your question say point blank "your response does not seem to apply to my question, what I asked was...." and ask again slowly and clearly.

I can only tell you what I've done, which happens from time to time with my team and my approach has worked for me. Although for the record I generally like who I work with, and they are generally respectful of me. I think some people are so eager to give their own 2 cents that they forget someone else is talking. Whenever I bring attention to the fact that they interrupted me there is almost always an apology for doing so.

By communicating that you were interrupted you are making things clear not just to your coworker but also the VPE. The VPE's perception of how you handle the situation is just as important as communicating clearly with your coworker.

And if this person is that big a distraction in the interview process I would either ask the VPE to sit in on an interview OR tell the VPE to not include this person in the interview.