This happened today in my 2nd play-through.
During Episode 3, on the train when Lee tries to get Kenny to stop the train. If you choose to stay silent throughout. Kenny will chuck Lee out of the cab door. Lee will go into the boxcar and find Katjaa, Clementine and Ben dead, and then Duck (as a walker) will push Lee out the train and you die.
It's quite amusing and I think you guys/gals should check it out.