Britain is facing a "collapse of authority" where young people no longer respect adults or institutions, a senior Conservative has warned.
Mr Duncan will give his speech to a think-tank in London
Shadow trade and industry secretary Alan Duncan said it was up to the Tories to "re-civilise" the country.
In a speech in London, Mr Duncan warned the UK would be "condemned to decline" if young people were not controlled.
His comments follow the fatal shootings of three teenagers in south London in the past fortnight.
"The greatest problem we need to address in Britain is that it is steadily becoming de-civilised," he told the Centre for Policy Studies think-tank.
Mr Duncan likened some young people in modern Britain to those in William Golding's novel Lord of the Flies, where a group of children descended into barbarism after being stranded on a desert island.
He called for school teachers to be empowered to "exert the control that too many parents are unwilling or unable to exert".
"The collapse of authority cannot remain undiscussed. If there is no fear of authority, there is no respect for it," he said.
"It cannot make sense in a civilised society for children of school age to face the discipline they need in court rather than in class or in the home."
Mr Duncan praised party leader David Cameron, who he said had "radically decontaminated the Conservative brand".
He said the party under Mr Cameron was championing a vision of social responsibility which "transcends worn-out divisions shaped by class, age and wealth".
Mr Duncan said he is more optimistic about the party's fortunes than he has been for 15 years.
"We can afford to be braver and if we are to see the social responsibility we are striving for, we must make sure that as politicians we show that courage now."