Would you inform the school?

Yeah I'd be reporting that incident to the head of the school. Simply because if her child is in the same school, there is a clash there.
The school should be made aware of the type of people they have working with their children and the fact that your friends child attends this school just puts the nail in the coffin.
She needs to email the head teacher and explain what happened and request that the teacher has nothing to do with the child. Hopefully the teacher will be suspended pending enquiries.
I'd also report it to the police to put it on her record at the very least, as it is assault.

Ah, the truth finally comes out!!!!!!

It is personal, very personal. About you and your feelings about this person.

I feel very sorry for her with someone so obsessed after her.

Where has anyone said the behaviour is fine?

Are you deliberately misreading?

This. There is never any excuse for spitting, but I do wonder what the friend said which upset the teacher. It may not be something which OP's friend wants everyone to know about! If it was related to her child or the school, then she would have made an appt to discuss it with the teacher and maybe the head at school during school hours, so I presume it's something personal/historical between them which is in no way related to the teachers job. And is therefore a private matter.

So the teacher spat?
Wow! That’s disgraceful behaviour from a professional who spends a great deal of time presenting themselves as a role model for kids.

I actually can’t think of a time in my entire life I would literally be so lost for words that I resorted in spitting at someone!

If deciding on whether to let the school know which type of person they have on their books, I would decide depending on what the argument was about tbh. If just a trivial thing, then yes, absolutely unacceptable to reach that level of assault, but say for instance your friend had slept with teacher’s husband then I think she got off lightly and no I wouldn’t inform the school.

I think they would be similar. The advice would be that if your friend felt threatened or in danger, then she should go to the police. Which was the advice you got?
Ultimately a women spat on her 'friend', it was not on school premises or directing affecting the pupils. Everyone has a certain level of conduct to uphold, as stated by the laws of our country. Their profession is only relevant if it has direct implications - such as if she was observed being rough with or intentionally harming a child, something which linked to abusing the power linked to their role.

This is so weird. Of course if you or your friend was spat at, you should report it to police. If there is CCTV camera and workers around (who I assume are neutral) then the police will do what they need to with that. If the third party witnesses have been involved in these historic grievances against the teacher or have some biases or there is no evidence other than their word that she spat, the police can't do anything with that, nor can the school.

I struggle to think why a teacher who had had complaints from a group of parents (maliciously or not) would be hanging around with them in public. The only reason this could have occurred if she was confronted or harassed in public. If you said that there is CCTV footage then this will be easy. Spitting is utterly unacceptable and disgusting and people should absolutely be called out on it. She will absolutely be reprimanded by her school as she should. This is the only action you need to take. You don't need to worry about anything more if your friend has reported everything and has evidence she can show the police/school. Just make sure you are separating factual information from your personal grudges against the teacher.

So true! I worked in a bar that a lot of teachers booked for their staff nights out and they were always absolutely unhinged. They made the freshers look like angles.

This thread is wild! I’ve never seen such a strident defence of teachers on MN lol.

I doubt a teacher would lose their job over spitting, it might be a staff conduct issue which OPs friend will not be permitted to know about - I think I would tell it the school I was OPs friend mainly because it would be extremely awkward to maintain a parent/teacher relationship when the teacher had spat at you, and the HT could mitigate that by something like establishing a comms plan if the teacher is the class teacher.

No you're not, you're hoping you can cost her her job by reporting it and playing up the idea that she's somehow unfit to be around children to justify yourself. If you want to be a bitch then go ahead and be a bitch but don't pretend you're coming at this from a place of virtue.

It’s not about your friend not being believed because the person who assaulted her is a teacher, it’s the fact there surely isn’t any proof other than he said/she said.
You seem to have a very unhealthy dislike of teachers.
I also don’t know anybody in my circle that is scared of teachers!

The kids at my son's school are always being told that they are representing the school at all times, especially when they are in uniform, even out of school hours, so why should it be a different rule for teachers? However, I think your friend should report to the police rather than the school and leave it to them to decide what to do next. You don't know what they were arguing about and what happened exactly, you weren't there, so you really shouldn't get involved, leave it to your friend to take things further. I understand you being upset as I wouldn't like someone who thought spitting at people in anger was acceptable behaviour being in a position of trust with my children, shaping their minds etc but if your friend feels she's been assaulted then it should be her and only her who reports it to the police.

"Discussion" or "confrontation" ?

If your friend was really upset by this she would have told the police. No point in going to school, the school will find out when the police investigate.
I'm more inclined to think you just want to cause drama at the school and think this a good way to do it.
I also think your friend would have said something pretty vile to get such a reaction, there's a reason why she hasn't reported it.
Your friend told you to leave it so leave it. Your friend is more than capable of reporting it to the police (not the school) if she wants.
I'd be interested to know though if you'd report anyone to their employer no matter what their job. What if it was someone at the supermarket and your friend shopped there? Would you go to their managers?

all because she could not handle what was being said
so what was said to take that level of alleged escalation?

I’m sure if the OP is going to tell the police and has the witnesses details .. AND CCTV no less - she will get her revenge.
OP you should stop pretending it isn’t you that was spat at.
Spitting is disgusting. But it isn’t always common assault, no matter how many witnesses there are. Just remember that. But good luck to you

Why on earth is your friend friends to this woman if she's so awful?!

I think knowing the context of the argument would be most enlightening.

Also, I’m not entirely sure what the police will be able to do unless there’s some proof. Otherwise, what stops your friend from reporting it, the teacher saying it didn’t happen and a couple of people who witnessed it to say it did but the police aren’t going to just believe them with no evidence surely?

Firstly, I can’t stand spitting. It’s gross. Having said that, I’m failing to see what on earth it has to do with you, partly because you weren’t even there and also because you clearly already dislike the teacher and you’re out to pull them down a peg or two.
You’re coming across like you’re a playground snitch.
It’s telling that your friend didn’t want to take things further until you started getting in her ear to report it.
That’s on the basis that this is real. It probably isn’t.

This.
You weren't even there and are just going off what you've been told.