I was the car behind the white car that crashed into the black car that did a u-turn.I was thinking that but your last paragraph is relevant.
We don't know how close the young driver was when the old bloke started to do his manoeuvre. If he suddenly started to turn and she was coming toward him it might have been impossible for her to stop. If he was doing it in the distance and she didn't slow or stop then it's her fault.
There was very little breaking done by the white car to the point I don’t think I seen the break lights so I also had to slam on even though I was a little bit behind her.
That being said, I don’t think there was much time to react anyways as the car doing the uturn seemed to pull out without checking. I have a feeling the light a little further up was red so he has seen that and decided the traffic was slowing/stopping anyways.
It makes me think that I should defo get a dash cam.