Can we terminate a manager who got drunk at our annual company event?

Q. Our organization has a four-day annual meeting for our managers, directors and leaders from 40 offices across the United States. The evening before the meeting ends, we host a large, fun, casual theme party. During this year’s party one of the sales managers from an affiliate office became so intoxicated that she had to be held up and escorted back to her room, where a hospital medical staff member stayed with her to make sure she was OK. The following day, she skipped the remaining meeting sessions and took an early flight home. Is this grounds for dismissal?