Is DD in the wrong here?

He's got a mark which someone left while defending themselves. He's got previous. I really don't see why this is an issue of concern. The real issue is that he's not a nice person, friends don't hurt each other.

Let's hope Alf no longer finds deliberately hurting your daughter quite so funny anymore.

Tell your DD she always has the right to defend herself.

With friends like Alf who need enemies.

She wouldn't be in any trouble with me. Someone deliberately doing something they know hurts (and risks causing an injury) and has been told to stop should expect an instinctive physical reaction - your daughter's scratch, a kick with her other leg etc.
He sounds annoying - is he actually a friend? Does she want to hang out with him?

teach her how and where to punch. People always seem to react so badly to anything that causes even a wee amount of blood.

Good I’m glad! She was defending herself!

I get why that worries you but if they hang out in a group won't the others back her up?

She needs to tell him that until he can learn to behave himself, he's no longer welcome in their group.
If you're concerned about him complaining then be pro-active and inform school and his parents. This has to stop. He needs to learn about boundaries otherwise his behaviour may escalate.
Your DD did nothing wrong, she reacted out of fear and pain. She has to have your backing to give her the confidence to stand up to herself.

For gods sake don’t make her apologise for defending herself against a boy who was touching her after repeatedly being told no. She should be praised for sticking up for herself.

In the adult world - fuck around and find out. Good on her for defending herself.

Well done to your daughter, she defended herself and had every right to do so.

Tell her you are proud of her and if Alf hasn't learned his lesson to do it harder next time.

Good for her, but I’d have had words with the school, his parents, and him, before now.

I'd be proud of her

Why is he only doing it to her? Is he a muppet that everyone else has been rude to but she’s been ‘kind’?

Nope. She is fine.

Teenage justice. It was very common back in the 70s, glad to hear it still survives.

Sorry OP but I'm struggling to understand why you're all such wet wipes.
The moment this boy touched anybody without permission - let alone hurt them he should have been cut out of the friend group.

What's with all this 'telling the teacher' nonsense? Why are they still hanging out with him? No way would I let any of my DC carry on like this. Unless you're going to drip feed some massive backstory.

No, I don't think she was in the wrong.

A) she has previously asked him not to do it,

B) it was self defence

You need to teach her better boundaries, she shouldn't be friends with someone who keeps hurting her. I'm glad she scratched Alf, he deserved worse.

Probably because when he tried it he got a smack in the mouth.
😉.

She wasn't in the wrong. Hopefully he'll think twice about putting his hands on her in the future! I wouldn't be happy with my daughter hanging around with someone who doesn't understand that no means no. Maybe she should re-evaluate the friendship.

So he's a 14 year old boy who repeatedly puts his hands on people (females) against their wishes, whilst knowing he's hurting them physically when doing so? He doesn't take "no" for an answer, even when told repeatedly not to do this to them, so has no respect for boundaries. Then, when a girl retaliates to physically stop him, he plays the victim, and gets verbally abusive?

This boy is a walking red flag, i'd be telling my daughter to cut all contact with him.
It's doing something to annoy/cause pain now, but what's to stop him applying the same behaviour in a sexual way in future?

So why isn't he doing it to the boys?

What is wrong with you that you hear your daughter has been assaulted and you're unhappy she defended herself?

I think I'd want to have a talk with her about why she is spending time with someone who is deliberately hurting her. That would really worry me.

Good for her. Tell her if he ever tries to get physical with her again to dish out a swift kick to the balls.