Shaping Employee Engagement and Emotional Intelligence

My surprise at seeing the thread of emails between my supervisor and one of my direct reports bordered on shock. I sat in the airport in Chicago on my way home from meetings with several of our strategic partners with time to check my emails.  I opened my email to see a stern prose from my boss chastising one of my direct reports.  I winced as I read through the original email.  Why my direct report had chosen to email her concerns to the entire group was beyond me.  Wisdom dictated that the candor of her observations required much more discretion than a group-wide broadside. Now instead of helping my employee process a valid observation and manage their emotion I had to manage up with the entire executive team and manage down to all my team who were now convinced that their feedback was unwanted and a potential liability to their career survival.

What would you do?