At 14 years old I could have champers, or some nasty spirit like tia maria, malibu or bacardi and coke (lots of coke!) on special occasions (birthdays, new year, christmas. It was never not allowed, I just don't think my mum wanted to waste her good wine on me at that age :c)
By 16 I was trusted to drink like an adult (an adult who doesn't drink just to get pizzed) and so going to the pub with friends was never something I think my parents worried about massively.
By 17 mum seemed to think it was acceptable for her to share the good wine with me :c)