North Wales police say the dispersal order, which came into effect in Bangor town centre yesterday, will prevent under-16s who drink, or cause a nuisance, from gathering in the town centre.
But Towler said imposing a “blanket ban” on all children and young people is a “heavy-handed and ineffective way of combating antisocial behaviour”.
“It demonises under-16s, isolates them from their communities, alienates them from police and spreads the misconception that all young people are troublemakers,” he said.
“I fail to see why such a drastic measure is necessary. Police already have the power to take action against those that are engaging in criminal behaviour in a public place.
"This measure holds the potential to criminalise all children and young people who are out at night, irrespective of their actions. How will this help to address the underlying problems that are at the heart of antisocial behaviour and build community relations?”
Police claim the move will help tackle antisocial behaviour such as groups congregating to drink at the locations or intimidating members of the public.
Inspector Simon Barrasford, speaking on behalf of North Wales Police and Gwynedd County Council, said: “Dispersal orders have proved an effective weapon against antisocial behaviour in other parts of the force and can demonstrate how partnership working can be most effective.
"Many people are working very hard to improve and regenerate the city centre as well as just wanting to enjoy their daily lives without being intimidated or harassed and I have no doubt dispersal orders areas will assist in that endeavour.”
Young people under the age of 16 must not be in the designated area between 9pm and 6am unless they are with a parent or responsible adult aged 18 or over.
The dispersal order will remain in place for six months, after which it will be reviewed.
Breach of the dispersal order could lead to three months imprisonment or a fine of up to £2,500.
