Don't avoid the conflict or don't start this lengthy e-mail exchange. That's what some people are resorting to now and you just dig a deeper hole for yourself. It takes a lot of practice and high-level communication skills to deal with a defensive person.

They may need to take a step back and get perspective. That might mean reaching out to others and ask how they've handled it. The thing not to do is to be reactive in the moment. You have to choose your words carefully, and human resources people really know this if they keep up with their employment law.

It does work, but it takes time. It's not a quick fix.