The last law and order crisis in Hong Kong was not during the Cultural Revolution disturbances of 1967. It was a decade later, when the police mutinied, staging mass demonstrations against the Independent Commission Against Corruption for its investigation of institutionalised corruption in the force.
The existence of this cancer had been hinted at in an inquiry into the 1966 riots - caused by local grievances, not Beijing - but nothing much happened until the creation of the ICAC.
This followed the prosecution of two expatriate superintendents who had acquired vast sums, and the rapid migration of numerous locally recruited senior sergeants. The police then showed that they believed themselves to be above the law, forcing governor Sir Murray MacLehose to back down and offer an amnesty. The crisis was brief but profound.
These episodes offer three lessons. First, they showed the dominant power of the police in a government of unelected bureaucrats and without its own army. In Hong Kong over the past four months, other officials have been notable for their silence while policy on the ground has been in the hands of the police.
From the first big rallies in June, it became evident that clearing the streets of demonstrators was a goal, not merely the protection of people and property. The cycle of aggravation saw pepper spray succeeded by tear gas, rubber bullets, beanbags and even live rounds.
In the absence of political initiatives, the police naturally assumed they were in charge. People on the streets were subject to the police, but the police themselves were subject to no formal oversight. Stirring the pot on both sides were rumours, false news, and maybe some truths about both black hands and provocateurs.
The second lesson is the role of official, preferably judge-led, inquiries with broad remits and powers to subject the government and other players to scrutiny. They take time, which allows tempers to cool.
The third is that an amnesty can work. It was humiliating for MacLehose to wipe the slate clean of serious crimes carrying long jail sentences for senior policemen, and many of the rank and file. But the amnesty enabled continuity in the police force while making it clear that the ICAC would keep a close watch, particularly to prevent the re-emergence of organised corruption.
Amnesties have a long history of resolving or at least ameliorating intractable issues. Recent examples include the Good Friday Agreement, which ended decades of violence in Northern Ireland.
South Africa's Truth and Reconciliation Commission showed that retribution for past crimes involving significant numbers in divided societies can only result in continuing cycles of violence. No one can pretend that there has been lots of justifiable violence on both sides in Hong Kong.
Something has to give, otherwise there is no end to social division and resentment against an unelected, unaccountable elite of bureaucrats, oligarchs and self-styled patriots insistent on punishing those who dare to challenge them, rather than noting the need for change.
In her policy address, Chief Executive Carrie Lam Cheng Yuet-ngor missed an opportunity to move towards a political solution to what has always been a political problem. If she really believes that mass protests are mainly rooted in housing issues, it shows just how out of touch she is.
For sure, the housing measures proposed are mostly sensible but unexceptional and might have been expected regardless of the bigger picture. The announced willingness to use the Land Resumption Ordinance to acquire public housing is years overdue. It remains to be seen if it will be forcefully used against the big landowners.
Dug into her bureaucrat's trench, she lacks even a periscope to see the wider world. Who else could, at this critical juncture of Hong Kong's history, praise herself for implementing 97 per cent of several hundred "initiatives" and promising another 200? There was no hint of understanding of resentment at the political, as well as money, power of big business and its connection to the deficit in democracy and accountability.
Nor was there recognition of reasonable popular expectations to maintain Hong Kong's identity within China in the face of pressures to integrate into the 70-million strong Greater Bay Area.
Likewise, the refusal to hold an independent inquiry into all the major issues of the past four months can only underline public scepticism. What is the government trying to hide?
After four months of turmoil, there have been no sackings of incompetent officials, no sense that there is anything wrong with the system. Classing demonstrations as illegal simply creates the need for more police and more weapons. Meanwhile, waving American flags in frustration at Lam's government naturally added to Beijing's intransigence.
Ahead now, without cutting a Gordian knot, there is the prospect of dozens of trials which will, by their nature, focus on police behaviour as well as the actions of demonstrators. This can also only mean additional pressure on the independence of the judiciary.
That independence not only runs contrary to the interests of the police in particular and the government in general but is anathema to a Communist Party which believes the judiciary should be the servant of state and party.
The policy speech was the last chance for Lam to show she could lead Hong Kong out of its mess. That knot must now be cut.
Philip Bowring is a Hong Kong-based journalist and commentator
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