(especially to people of dissimilar age, eg the taxi diver) but surely if you talk to someone for a while you would have doubts
That is a good point. The taxi driver is likely to be in the range 30 to 55. He won't have given her more than a cursory glance. He has no axe to grind unlike the man (and possibly the police ) but his evidence may well be very unreliable.
So far as the girls, I cannot fathom how the parents /guardians of either girl allowed them to be out that late unless each thought there was a sleepover at the other's - although the report refers to them both travelling to Edinburgh. I wonder if anything happened with the 13 year old friend?
Teenagers will have sex and generally girls are not interested in younger boys. I don't have a problem with 16 year olds having sex with 19 year olds ; I don't have a problem with one night stands.
I do think it extraordinary that he did not twig that it was a remarkable coincidence that she happened, conveniently, to be 16 and that he did not pick up from their conversation that she was 12.
I'm trying to recall what I or my son were like at 12. I'm pretty sure that no matter how articulate we were, we would not have passed as 16. The girl was presumably drunk which must also have affected her ability to act older than she was.