In Season 2, Episode 15 ("Boys and Girls") of The Office (U.S. series), the warehouse workers in the Pennsylvania branch of the New York-based company begin deciding to unionize.
Vice President of Sales Jan Levinson learns of the workers' discussion from Regional Manager Michael Scott, who is her subordinate and their supervisor. Jan then tells the workers that the company will terminate their employment if they unionize.
Jan (to Michael): What? A union?
Michael (to Jan): Let's be rational here. What are the pros, what are the cons?
Jan (to Michael): The cons are that everyone will lose their job, Michael. Everyone. Office, warehouse. What do you think the pros are here?
Jan (to workers): Excuse me. Excuse me. I'm told there's been some interest in forming a union, and that Michael supported it. Obviously he's not a friend of yours, because he didn't tell you the facts. So let me.
Jan (to workers): If there is even a whiff of unionizing in this branch, I can guarantee you the branch will be shut down like that. (Snaps) They unionized in Pittsfield, and we all know what happened in Pittsfield. It will cost each of you a fortune in legal fees and union fees and that'll be nothing compared to the cost of losing your jobs. So I would think long and hard before sacrificing your savings and your futures just to send a message.
My understanding was that U.S. employees could not be fired for forming a union.
However, if that were so, this scene would square oddly with the rest of the series, as entire episodes are devoted to displaying that company's reticence towards lawsuits.
A. Was it illegal for Jan to state this threat to their jobs?
B. Would it be illegal for the company to carry out the promised actions?
EDIT: Clarified who the conversations were with.