Hong Kong police have been pushed and pulled in all directions during weeks of pro-democracy street protests, obeying orders to clear protest sites, allow protest sites to stay put, push back demonstrators and protect them from attack.
With no end to the standoff in sight, the police, long known as "Asia's finest," risk being cast as enforcers for an unpopular central government in Beijing or failing in their duty to ensure the city remains one of the safest in the world.
"Your friendly 'bobby on the beat' image ... has been taken for granted in Hong Kong," said Steve Tsang, head of the School of Contemporary Chinese Studies at the University of Nottingham in England.
"If the police start actually using force then all those things that have been built up ... will go out of the window."
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In signs of goodwill, police have been seen washing out protesters' eyes with bottled water after using pepper spray. Protesters have used their trademark yellow umbrellas to protect police in sub-tropical downpours.
But the force seems to be caught between a rock and a hard place, with uncertainty creeping into tactics. The use of tear gas only drew more demonstrators on to the streets. Protesters have since been allowed to block some of main thoroughfares, illegally, sparking anger from tradesmen and small businesses whose livelihoods have been hit.
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China took back control of the former British colony of Hong Kong in 1997 through a "one country, two systems" formula which allows wide-ranging autonomy and specifies universal suffrage as an eventual goal.
But Beijing said in August it would effectively screen candidates who want to run for city leader, which democracy activists said rendered the notion of democracy meaningless. Student-led activists have since taken to the streets.
When police stepped in to protect protesters from attack by opponents, they were swiftly accused of co-operating with triad criminal gangs, failing to make arrests and helping some of the assailants escape the scene.
"People are saying the police are switching back to being licensed triads," said a protester who gave his name as Wong.
Their reputation took a further battering when several officers were caught on video beating and kicking a handcuffed protester as others kept lookout.
The triad accusations hark back more than four decades to an era of violent unrest fomented by the Chinese Communist Party in the grips of Mao Zedong's Cultural Revolution and to a colonial-led force that was mired in graft and brutality.
The then Royal Hong Kong Police worked hard to clear that stain and earn a place among the world's most trustworthy forces.
According to the World Justice Project's 2013-14 rule of law index, only police forces in Japan, Singapore and Denmark ranked higher in providing order and security. Hong Kong police were also fourth - behind Finland, New Zealand and Qatar - in a World Economic Forum 2013-14 global competitiveness report that gauged the reliability of police services.
"Great deal of restraint"
Criticism of Hong Kong police was misplaced given the "quasi-military" tactics adopted by some countries, including the United States, said Allan Jiao, professor in the department of Law and Justice Studies at Rowan University, New Jersey.
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"Hong Kong police have exhibited a great deal of restraint in the face of the protests and their performance compares favourably internationally," he said. "Occupying major street areas for a prolonged period of time would not be tolerated in the U.S. or U.K."
In Mong Kok, a crowded area where market stalls and massage parlours are neighbours to jewellery shops and noodle restaurants, frustrations boiled over when protesters charged police one night, reoccupying two busy streets.
The next evening, police reinforcements weighed into the pro-democracy crowd with shields, batons and boots. Unusually, police hurled back insults that would typically have gone unanswered.
"We have been trained to be patient and self-disciplined. But sometimes tolerance has a limit, especially when people are continuously using foul language," said one constable who declined to be identified because he was not authorised to speak to reporters.
Morale was at an all-time low among junior police, the South China Morning Post cited Junior Police Officers' Association chairman Joe Chan as saying. In-house police counsellors were visiting frontline officers to provide support, the Police Public Relations Branch said.
"Officers have to work for prolonged hours to handle large number of protesters and to face provocation, insult, attack and groundless allegations against them by radical trouble-makers," it said in emailed answers to questions.
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If there is a precedent for what the force is facing, it is the 1967 communist-led riots, said Kam Wong, an associate professor of criminal justice at Xavier University in Cincinnati and a former Hong Kong police inspector.
What started out as labour disputes at a plastic-flower factory and elsewhere turned into a fully fledged attack on British rule. When an outspoken radio host was doused with petrol, set ablaze and killed by assailants believed to be aligned with the rioters, public opinion turned and the police moved in, Wong said.
The people at the time finally felt that enough was enough, he said. "The police needed to take action."
There has been no violence on the scale of 1967 over the last few weeks. But growing frustration over chronic congestion and lost business as the protests drag on may yet hand the police a mandate to clear the demonstrators off the streets.
"The use of batons at close quarters, the use of tear gas - all these things have undone the good work re-establishing public trust in the Hong Kong police after the 1960s," said Carol Jones, a professor of socio-legal studies and criminology at the University of Wolverhampton.
"I think a whole generation now will no longer trust the police."