The legal age for you to drink or buy alcohol is 18 years old.
[s155 Sale of Liquor Act 1989]

If the police find you drunk in a public place or trespassing on private property, they can take you into custody and take you back home or to a shelter if they think you will:
- hurt yourself or hurt others.
- be unable to protect yourself from getting hurt.
- cause a large amount of damage to any property.
[s 36 Policing Act 2008]


Now, lets see what the law says about alcohol in pubs, parties and with driving:
Alcohol in Pubs
Alcohol in Parties
Alcohol and Driving