Thank you for trusting your question to JA today. I am a licensed attorney with over a decade of law practice and nearly 20 years of experience in the legal field. I’m happy to be of assistance.
Can he get fired for telling you who to hang out with? Sure. There is nothing illegal about the employer deciding that that was not appropriate and terminating the supervisor on that basis.
Now, must he be fired? No, there is also no law that states that the supervisor must be fired or even disciplined for what he did.
So, the employer here can take what action they choose against the supervisor, or not action at all, and any of those results would be legal.
However, your facts here indicate another issue. You stated that you lost track of time and the supervisor threatened you based on that. So, if you did try to get the supervisor into trouble for telling you who you can't hang out with (which I already explained was not a legal basis forcing the employer to respond), the supervisor could just state that the real issue was that you were late from a break and that is why you were threatened, not who you were hanging out with.
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