In a move that will be an acid test of the Hong Kong legal system’s independence, a group of pro-democracy politicians has asked the courts to rule on the legality of the ban on face masks.

The mask ban, which is based on a colonial-era emergency law and came into effect at midnight on Friday, triggered an overnight rash of widespread violence and destruction in the city.

Fires were lit and an off-duty police officer shot and wounded a teenage protester.

In a first test of the legal system, two activists failed to obtain a court injunction on Friday against the ban on face coverings, which the government says make it tough for police to identify radical protesters.

In a second bid, a group of 24 legislators filed a legal appeal to block the anti-mask law on wider constitutional grounds.

Lawmaker Dennis Kwok insists the mask ban is illegal. Photo: Wikicommons

Legislator Dennis Kwok accused the city’s pro-Beijing leader, Carrie Lam, of acting in bad faith by bypassing the Legislative Council, Hong Kong’s parliament, when she invoked the emergency law.

“This is a ‘Henry the Eighth’ situation. This is basically ‘I say what is law … and I say when that ceases to be law’. That’s not how our constitution works,” he said.

The court, which activists see as a pawn of China, will hear the case on Sunday morning.

Lam has said she will seek the council’s backing for the law when its session resumes on October 16, and she has not ruled out further measures if the violence continues.

In a televised address broadcast as protesters again marched in masks on Saturday, a solemn Lam described Hong Kong as “semi-paralysed” and reiterated the mask ban is needed to stop the violence.

‘Drastic measures’

“The government needs to take drastic measures to say no to violence, restore peace in society, protect citizens’ right to continue their daily lives and freedom, not allowing a small group of rioters to destroy it,” Lam said.

Many shopping centres, shops and the entire MTR network of subways and trains that usually handle more than four million trips a day shut on Saturday following the overnight rampage.

Many peaceful protesters say violence has become a means to an end, the only way for young masked protesters to force the government to bend to clamours for full democracy and other demands.

But the teen’s shooting on Friday night – the second victim of gunfire since the protests began in early June – stoked fears of more bloody confrontations.

An 18-year-old protester was shot at close range by a riot police officer on Tuesday.

Police said in a statement on Saturday the 14-year-old, who was hospitalised with a gunshot wound on his thigh, has been arrested for participating in a riot and assaulting a policeman.

Police have said they are still investigating exactly how he was shot.

-with AAP