Marie’s Answer: Given a little authority, power-loving people often become petty tyrants. But while Cindy’s position may have gone to her head, your supervisor is actually the responsible party. As his assistant, Cindy only has the authority that he is willing to delegate. So either he has sanctioned her actions or he isn’t supervising her properly.
Despite the open-door policy, meeting with the vice president would not be wise. Your supervisor will view this as going over his head, and he will not appreciate it. So you need to talk with him directly. For this conversation to succeed, however, you must not complain about Cindy. Your goal is simply to define her role.
For example: “I’m a little confused about when to take direction from Cindy and when to come to you. Can you help me understand exactly what a team lead is supposed to do?” If his description matches Cindy’s behavior, then you need to adjust.
But if his expectations seem different, ask for clarification. Should you notify Cindy when you go on break? What should you do when her instructions conflict with his? If your boss is halfway bright, he’ll get the message.
For suggestions on how to bring issues to your manager, see How to Complain to Your Boss.