The specifics if this case notwithstanding (I recognize that communications about workplace conditions are protected), if someone was on a slack channel, bulk emailing other employees undermining and disparaging their manager, were asked to stop and they didn’t, isn’t that grounds for termination?
They’re free to speak and tweet about it all they want. They’re just no longer an employee.
AIUI, if you want to enforce rules like that they need to be uniform. Eh you can say “business communication only, only email people who need to know, don’t spam, etc”. You can’t allow someone to sell Girl Scout cookies but then not discuss working conditions.
They’re free to speak and tweet about it all they want. They’re just no longer an employee.