The poor woman in the case I saw thought she was having a private chat to a family member, and was mortified that it was public. She hadn't mentioned a child by name, but had said something mildly derogatory about the kids in general I believe.
It does have interesting "facets", such as freedom of speech when off
the job, assuming the teacher was off the job.
And, to me - it also speaks to the state of affairs of education in this country. Teachers, in general, belong to the largest union in the US (NEA) and complain on a consistant basis about their pay, not
their inability to teach due to the restrictions placed on them by policies, regulations, and laws - many of which the NEA has had a hand in. The NEA publically stated they "will worry about the children when they can vote in union elections." No apologies given and little outrage.
So, if a teacher voluntarily wants to teach under those conditions, belong to a union such as that, fine. It does not absolve them YET of any and all unprofessional behavior. This parent will not win, mark my words....the teacher will not lose their license. At best she will get a PAID leave of absence.