Demos said they should face community service, social shaming or be banned from shops in order to help tackle harmful drinking by the under-18s.
Adults who get caught breaking the law and help children buy alcohol should have to contend with being “named and shamed” in prominent posters by the shop counter and banned from local off licences, according to suggestions in Demos’s Sobering Up report.
Demos also argues that police should do more to enforce on-the-spot fines and prosecute adults who give under-age drinkers a helping hand.
While the current on-the-spot fine is £90, police potentially have the ability to impose a maximum fine of £5,000 for people convicted of purchasing alcohol on behalf of a child, Demos said. It added that health select committee figures show only 16 people were successfully prosecuted over a four-year period.
Report author Jonathan Birdwell said: “All the evidence shows that under-age drunkenness increases alcohol risks later in life. The problem is especially severe in some parts of the country, such as Liverpool, Birmingham and Leeds, which have the highest numbers of under-18s being admitted to hospital due to alcohol.
“Our research suggests we need a tougher, smarter approach. This includes threatening parents who buy alcohol for their children to drink unsupervised with ‘social shaming’ like community service.
“Giving drunk and disorderly people entering city centres a ‘yellow card’ and denying them entry or forcing them to sober up would also moderate excessive pre-loading by denying people the fun night out they had planned.”
The report found that 33 per cent of 11 to 15-year-olds admitted obtaining alcohol in the previous four weeks and 19 per cent were given it by parents. The same number said they had managed to get alcohol from their friends.
A total of 13 per cent of teenagers said they had asked someone else to buy alcohol for them, while three per cent had illegally purchased it from a shop themselves.
The report recommends police form “booze borders”, refusing entry into city centres for very drunk individuals in areas with high levels of alcohol-related crime or health problems.
Such a scheme has been trialled in Watford, and Demos believes the idea could be rolled out as an effective deterrent elsewhere – either turning drunk individuals away, issuing a warning, or making them sober up in a designated area.
It was also argued that health information campaigns should be targeted at parents to try and help shift attitudes towards under-age drinking.
Elaine Hindal, chief executive of the alcohol education charity Drinkaware, said: “Drinkaware works to support parents of in their position as positive role models when it comes to alcohol.”