On 26 April last year, after the longest court case in British history, the jury at the new inquests into the 1989 Hillsborough disaster finally delivered their verdicts. They determined that the 96 men, women and children crushed to death at the FA Cup semi-final between Liverpool and Nottingham Forest had been unlawfully killed. They had died principally owing to the serial failures of South Yorkshire police – and specifically the gross negligence of the officer in command, chief superintendent David Duckenfield – in their duty to look after the safety of the 54,000 people attending the match.

The landmark findings blew away a ruthless 27-year campaign waged by the South Yorkshire police force to blame the victims – people at the match supporting Liverpool – for having caused the disaster, alleging that they were drunk and behaving recklessly. The six women and three men of the jury – who had heard harrowing, furiously contested evidence for two years – vindicated the bereaved families’ long battle against the police’s lies and against the first inquest, which, in March 1991, to the families’ enduring outrage, had delivered a verdict of accidental death. This time, the jury exonerated the supporters of Liverpool completely, finding that the behaviour of the spectators had not contributed to the disaster.

The false case, constructed by a police force that had grown increasingly powerful through its policing of the social and industrial strife of the 1980s, was finally demolished. After these revelations, a long-buried question rose in prominence and urgency: how had this northern English police force, over the course of the 1980s, become so hardened, high-handed and detached from its citizens?

In 2012, the Guardian had made the link with a previous South Yorkshire police operation, this one against thousands of striking miners, which took place near Rotherham on 18 June 1984 and was notoriously dubbed the Battle of Orgreave. Scenes of police violence, including horse charges and officers beating miners with truncheons, dominated television news that day. No police were charged for their actions. Instead, the incident led to the prosecution of 55 miners who were arrested at Orgreave and charged with riot.

But the prosecutions collapsed after the trial of the first 15 fell apart a year later, on 17 July 1985. What the court case had revealed was not the guilt of the accused, but rather the failings of the South Yorkshire police operation. The miners’ lawyers accused the police of bloody, unprovoked assaults at Orgreave, then of perjury and perverting the course of justice in compiling the case for the prosecutions. It was, according to Michael Mansfield QC, “the biggest frame-up ever”.

Even after the trial collapsed, following revelations of what appeared to be serious police malpractice, Margaret Thatcher’s government opposed any inquiry. Its support for the police was unconditional. In March 1985, just after the National Union of Mineworkers’ (NUM) strike had ended, Thatcher attended a drinks party at the Home Office to congratulate the chief constables of forces who had helped defeat the miners.

The South Yorkshire police force was not held to account, nor was there any reform. Four years later, Peter Wright, the chief constable who had overseen the operation at Orgreave, was still in charge. It was Wright who was responsible for the catastrophic appointment of David Duckenfield to police the match at Hillsborough on 15 April 1989, and for the campaign after the disaster to deny responsibility and blame the victims. Many of those whose loved ones were killed in the disaster came to believe that the force’s inhumane response was bred and given official sanction by the harsh policing of the miners’ strike. For years, they fought for accountability.

Last April, when the Hillsborough verdicts were delivered, Theresa May was home secretary. During her six years in office, the Hillsborough families, who always felt Thatcher’s government had been complicit with the police in the original denial of justice, found May to be surprisingly supportive.

May had taken office just as the Hillsborough Independent Panel (HIP), an initiative of the previous Labour government to examine all police and other documents relevant to the disaster, was starting its work. In September 2012, she and David Cameron, then prime minister, fully accepted the panel’s report, which was damning of the South Yorkshire police and exonerated Liverpool supporters. Then, in December 2012, after the bereaved families’ 21-year fight against official indifference and opposition, the government itself applied for the 1991 Hillsborough inquest verdict to be quashed. May’s Home Office funded the families’ legal costs throughout, including at the new inquests, at which their lawyers had to challenge the same police evidence against Liverpool supporters all over again. Margaret Aspinall, the chair of the Hillsborough Family Support Group, whose 18-year-old son James was one of the 96 dead, says she found May courteous, attentive and sympathetic.

Against expectations for a Conservative home secretary, May developed a tough stance against police wrongdoing, delivering confrontational speeches about the need for reform to dumbstruck Police Federation conferences. According to her biographer Rosa Prince, May was encouraged to pursue this agenda, and to shape the presentation of herself as she still does – as a supporter of “ordinary working-class people” – by her chief of staff Nick Timothy.

In parliament on 27 April, the day after the Hillsborough verdicts, May condemned “the authorities” for their campaign of “hostility, opposition, obfuscation” and blame. She said lessons had to be learned, and that the government would continue to support the families in their “quest for justice.” Andy Burnham, Labour’s shadow home secretary, who had initiated the HIP process in 2009, welcomed the jury’s findings, then called for an inquiry into the Orgreave scandals. “I promised the families the full truth about Hillsborough,” he said. “I do not believe they will have it until we know the truth about Orgreave.”

May noted in reply that she had met Orgreave campaigners in 2015, and had received their submission for an official inquiry. “That is being considered,” she said.

In the following days, strong signals that May had indeed decided to hold an Orgreave inquiry grew in momentum. On 17 May, just three weeks after the Hillsborough verdicts, May went to the Police Federation’s annual conference and made another forthright speech, stressing that the police must accept the “enormity” of the jury’s determinations. She delivered a stern lecture, stating – in a tone of certainty that has since become more familiar to the nation – that inquiries into historic police wrongdoing are a fundamental necessity.

Everybody, she said, must understand “the need to face up to the past, and right the wrongs that continue to jeopardise the work of police officers today. Because historical inquiries are not archaeological excavations. They are not purely exercises in truth and reconciliation … they are about ensuring justice is done.

“We must never underestimate how the poison of decades-old misdeeds seeps down through the years and is just as toxic today as it was then. That’s why difficult truths, however unpalatable they may be, must be confronted head-on.”

On the very same day, the website Conservative Home published an article by Nick Timothy arguing that there should be an inquiry into the Orgreave allegations. “Since 2010 the government has shown it understands that justice must be done no matter how long it takes, and that to get things right in future, we have to understand what has gone wrong in the past,” he wrote.

A month later came the vote for Brexit. May, who had spoken with certainty that Britain would be better remaining in the European Union, stepped over her fallen rivals and grasped the opportunity to move into No 10. Timothy rejoined her as chief of staff, from his break as director of the Free Schools Network.

Once installed as prime minister, May’s fervent belief in righting wrongs and fighting past injustice – the need to “get to the bottom of cases like Orgreave,” as Timothy had argued – became rather lost.

On 31 October, May’s home secretary, Amber Rudd, declared that there would be no Orgreave inquiry. May had argued that historic inquiries are vital for justice and restoring public trust in the police. Now, in a breathtaking U-turn, her government was arguing that the passage of time itself meant that Orgreave did not have to be addressed, because policing practices had been reformed since the 1980s. “There would therefore be very few lessons for the policing system today to be learned from any review of the events and practices of three decades ago,” Rudd said.

Rudd further explained this reversal of principle by saying that she could not conclude with “certainty” that had the Orgreave scandals been addressed, the deaths of 96 people at Hillsborough would not have happened. Nobody, of course, can say that with certainty – the families simply believe that their loved ones might have been kept safe, had the force been reformed after such large-scale malpractice. Rudd was misrepresenting their argument. She argued there was “no miscarriage of justice” because none of the miners charged with riot was ultimately convicted. But it was her final justification that drew the most outrage from Orgreave campaigners and the families of the 96 people unlawfully killed at Hillsborough: “Ultimately,” Rudd said of Orgreave, “there were no deaths.”

The thinness of these justifications – particularly the idea that, if police malpractice is to be held to account, people now have to die – led many to conclude that May had reverted to standard, unconditional Conservative support for the brutal suppression of the miners’ strike. The decision delivered the opposite of the position she had previously been advancing: she was now tolerating historic police malpractice and declining to confront “unpalatable” truths. The more that is known about Orgreave, and about the unlawful killing of 96 people so soon afterwards at Hillsborough, the clearer the outrage is – yet “the poison of decades-old misdeeds” was, after all, to remain untreated.

Orgreave, the site where Arthur Scargill, president of the NUM, called for a mass picket on 18 June 1984, was not a mine, but a hulking, smoking plant set in fields outside Rotherham. Its workers processed coal into coke for the furnaces of British Steel’s vast factories 40 miles east across South Yorkshire in Scunthorpe. Yet Orgreave became the infamous centrepiece in a year-long clash of historic forces, a strike that marked the beginning of the end for mining and the other great heavy industries on which Britain’s economic power was founded. What happened at Orgreave was not simply the most violent police behaviour ever seen in a modern industrial dispute, but the culmination of a concerted political campaign to diminish the strength of trade unions.

The execution of that strategy since, and the release of official documents, has clarified how Margaret Thatcher’s Conservative party prepared in advance to face and defeat a strike by the NUM or another of the mass-membership unions in industries such as steel, the railways or utilities, which were all then state-owned. Scargill was himself a veteran of a fateful 1972 confrontation in which the NUM had been considered victorious over Edward Heath’s previous Conservative government. During that miners’ strike, which forced power cuts and a three-day working week, Scargill led mass pickets that descended on the Saltley coke works in Birmingham. The police were not at Saltley in great force, and under pressure from the pickets, they eventually allowed the gates of the plant to be closed. Heath’s government conceded significant pay increases for miners. It was a landmark victory for the NUM and a principal reason for the Conservative party’s defeat in the 1974 election. In opposition, the Tories nursed a strategy for privatising the nationalised industries by fragmenting them and selling them off to the corporate market – and for revenge: to break the negotiating and mobilising power of the unions.

At the NUM’s cavernous headquarters in Barnsley, the assembly hall is lined with old books and draped in the hopeful, defiant banners of local branches whose years of small subscriptions built community welfare and collective strength for generations of workers. But this once-formidable organisation is now a shell. The current general secretary, Chris Kitchen, who was at Orgreave as a 19-year-old on strike, says that most of the work now is handling old miners’ injury claims, pensions and the other leavings of a mighty industry. Britain’s last deep coal mine, Kellingley, closed its gates for the final time in December 2015.

Reflecting on the Thatcher government’s determined defeat of the 1984-85 strike and the closure of the industry, Kitchen, like many former miners, refers immediately to the strategy mapped out in the “Ridley plan”. This plan to deal with the nationalised industries was worked up by a Conservative party policy group while the party was still in opposition. The group was chaired by Nicholas Ridley, who, after Thatcher won the election in 1979, became her transport minister, and later oversaw manoeuvres during the miners’ strike. An old copy of Ridley’s 26-page report, handed over forlornly by Kitchen, makes explicit recommendations to aim for profitability by privatising coal, steel, railways, ports and other industries that had become publicly owned after the war, and to “break up the power of monopolicy (sic) public sector unions”.

Arthur Scargill leads the miners at Orgreave. Photograph: Don McPhee/The Guardian

Reading it 40 years on, with knowledge of the vast privatisations and deindustrialisation of Britain that followed, the report’s language is alarmingly violent and antagonistic. Produced as a planned industrial policy by a political party aiming to be elected as the next British government, it spoke of waging a war with its own population. In a confidential annex, entitled “Countering the Political Threat”, the report foresaw “battles” with unions, referred to workers in the nationalised industries as “enemies” and “communist disruptors” who would try to “destroy” the privatisation plan. Pondering how to inflict a landmark defeat on the unions – which, it said, would see privatisation, job losses or wage restraint as a “casus belli” (cause for war) – the report actually suggested that “we might try and provoke a battle in a non-vulnerable industry [one not vital for generating power], where we can win”.

The plan cited mining as a “vulnerable” industry, because coal was used in the production of electricity, but assessed it as most likely for an “attack” by its union. So the report recommended preparing defences: building up coal stocks and recruiting in advance non-union lorry drivers who would be willing to defy picket lines and move supplies around the country.

The annex also recommended strengthening the police, then mobilising them against industrial strikes. “It is also vital … that on a future occasion we defeat violence in breach of the law on picketing,” the Ridley plan stated. “The only way to do this is to have a large, mobile squad of police who are equipped and prepared to uphold the law against the likes of the Saltley Coke-works mob.”

After Thatcher’s 1979 election win, following Labour’s own struggles with union strikes and wage demands in the 1978 “winter of discontent”, the Conservative government effectively implemented the Ridley plan. The National Coal Board (NCB), the state-owned agency that ran the country’s 173 mines in Yorkshire, South Wales, Lancashire, Durham, Scotland, Nottinghamshire, Kent and other coalfield areas, employing 187,000 people, stockpiled millions of tonnes of coal in preparation for a strike.

Thatcher had appointed the NCB chairman, Ian MacGregor, from British Steel, where he had emerged from a 14-week strike in 1980 to halve the work force. MacGregor made his name in the US, where he had aggressively broken the strength of the United Mine Workers’ union in Wyoming in the 1970s.

On 5 March 1984, MacGregor sparked the NUM strike with the announcement that 20 mines had been designated uneconomical, and would be closed, causing the loss of 20,000 jobs. Miners at Cortonwood colliery, in South Yorkshire, one of the mines slated for closure, staged the first walkout. Scargill argued there was really a plan to close more than 70 pits, shrink the industry and shed thousands more mining jobs than that.

Kitchen and many former miners believe that MacGregor’s closure plan knowingly provoked Scargill and the NUM, the stockpiling and other preparations having been made. The announced pit closures were made at the start of spring, when demand for coal would be low.

“People wonder now whether we might have held back, tried to negotiate, to get through the summer, rather than react,” Kitchen says. “There are still two sides to the argument, and different views of Arthur Scargill and his tactics, but miners believed, justifiably, that their pits and jobs were under terminal threat, and we had no choice but to fight it.”

Orgreave gradually became a focus for picketing, after the NUM came to believe that the NCB was abusing an agreement between the union and employer for the transport of just enough coke to keep the Scunthorpe furnaces firing. There were some outbreaks of violence, and the response of South Yorkshire police escalated. On 30 May 1984, Scargill was famously arrested at Orgreave and charged with obstruction, for which he was later fined £250. The arresting officer, John Nesbit, was on duty five years later at Hillsborough, where after the lethal crush in the Leppings Lane “pens”, he led a line of police officers who helped pull the dead and injured out.

Scargill called for a mass picket on 18 June, and committed union members arrived in cars and coaches from coalfield areas all over the country. Kitchen believes, as do many others, that they walked into a prepared operation by South Yorkshire police that was intended to inflict a brutal battering. Official documents from the time reveal that Chief Constable Peter Wright himself commanded a plan in advance to charge arrested miners not with minor public order offences such as affray, but with the ancient and serious criminal offences of riot or unlawful assembly.

It was a hot, sunny day, and the miners who arrived from early morning were mostly wearing T-shirts, jeans and trainers. As the men and their lawyers would point out at trial, they did tough, dangerous work, for which they had to wear helmets, steel-toed boots and protective clothing, but unlike the police, they did not come dressed for a riot.

In hindsight, many are suspicious of the ease with which the police allowed them to reach South Yorkshire. By that point in the miners’ strike, police routinely set up roadblocks all over Yorkshire and Nottinghamshire, turning miners back on the M1 on the grounds that they were going to commit a breach of the peace. That day, says Kitchen: “We were all guided in, told where to park, led into that field. That makes us believe it was pre-planned to have us there, and give us a hiding.”

Under cross-examination a year later, Assistant Chief Constable Tony Clement denied that there was any intention to attack the miners, but made clear that the police were ready for violence. “If it was going to be a pitched battle, it was going to be on my terms,” he said.

Giving evidence at the prosecutions, Clement said that at Orgreave he had been in command of 4,600 officers, from 18 different forces. South Yorkshire police itself later officially put the figure at 6,000. Clement said he had 186 police support units (PSUs), whose role was to break up public disorder, made up of an inspector, a sergeant and 20 constables. There were 42 horses, whose mounted officers wore helmets and carried staves twice as long as truncheons. Police with dogs were stationed at the side of the long field in front of the plant. There were 345 men with riot gear including short, round shields and truncheons – the first time they had been used on the British mainland. It was also the first time that police in riot gear with long, thick plastic shields had ever been deployed in South Yorkshire.

Ranks of police face the picket line outside the Orgreave coke works. Photograph: PA Archive

They were stationed in massed ranks at the bottom of the long field, in front of the road along which the convoy of empty lorries would arrive, fill up with coke inside the Orgreave plant, then leave again for Scunthorpe. Workers had a legal right to picket, to persuade others to show solidarity by not working themselves, but that did not legally extend to intimidating people or physically stopping vehicles. The role of the police in an industrial dispute was officially not to take the side of the employer or government, but to maintain law and order. The rough compromise reached on most picket lines was a “ritual push,” where miners would make a show of trying to push through police lines, without expecting that they would succeed; the police would hold the line, then relative calm would prevail again. But at Orgreave, the police did not just stand firm against the strikers; they responded with mounted charges into the crowd, and with truncheons.

At Orgreave, as at Hillsborough, the version South Yorkshire police told on the day became the accepted narrative for years – even though it was wholly one-sided and contradicted the reality that the public saw on television. At Hillsborough, the enduring images were of injured, traumatised young Liverpool supporters emerging from the crush and making strenuous efforts to save others. They ran with dead and injured people on advertising hoardings, because the police and ambulance response was so slow and disorganised. Yet the stories told mercilessly by the police that “the fans” had been drunk and misbehaving still stuck.

The footage from Orgreave showed police on horses charging into defenceless men, and one officer repeatedly lashing a miner, Russell Broomhead, over the head with a truncheon. There was also the shocking photograph of a woman, Lesley Boulton, seemingly about to be smashed across the head with a long stave wielded by a police officer on a horse. She was pulled to safety, but many of the newspaper pictures of arrested miners showed them bleeding down their bodies from nasty wounds to their heads.

And yet the established view, even now, is the one Clement and South Yorkshire police told the media on the day: that it was a “battle”, that they were victims of violent rioters and responded only proportionately. Miners forever resent the BBC news coverage, which showed miners throwing stones and then the police charging; in fact, that footage happened the other way round: the miners were responding to being charged at by police. The miners always said that the police had charged on horses, and attacked them, without justifiable provocation.

But on the night, with these disturbing scenes of police violence bruising the news, Thatcher did not pause for fact-finding or call for an investigation. She came down on one side only, describing the miners as a mob. A note the following day, by her policy advisor David Pascall, was absolute in its judgement. Describing the miners as “Scargill’s shock troops,” it said: “Violence and intimidation … on the scale which we saw yesterday at Orgreave are unacceptable and an affront to both the civil and criminal law.” What had happened, Pascall continued, had been “mob violence”.

That same word has been used by Sir Bernard Ingham, Thatcher’s press secretary, to describe Liverpool supporters at Hillsborough, ever since Wright and other police officers briefed him and the prime minister the day after the disaster. Over more than two decades Ingham – despite the findings of Lord Justice Taylor’s official inquiry, which rejected that narrative, and even after the verdicts at last year’s inquests – has maintained that he “learned on the day”, from police, that the supporters were “a tanked-up mob”.

The South Yorkshire Police Committee, the local authority body responsible for oversight of the force and its budget, was, however, horrified by the police violence. Its chairman, George Moores, talking to ITV’s World in Action programme, described the behaviour of some officers as “deplorable; sheer hooliganism by yobs in uniform”. The committee resolved to restrict Wright’s budget for horses and dogs, but the most senior figures in government responded by giving Wright their total support.

In a note on 4 July 1984, just three weeks after Orgreave, Andrew Turnbull, Thatcher’s private secretary, wrote to a Home Office official: “The prime minister … agrees that the chief constable of South Yorkshire should be given every support in his efforts to uphold the law.”

Ninety-five miners had been arrested; 55 were charged with riot. Leon Brittan, then the home secretary, publicly stated that miners convicted of riot should be sentenced to the maximum term in prison for that offence: life.

The Thatcher government had, as planned, strengthened and allied itself with the police in the years before the strike, awarding officers generous pay rises, while workers in nationalised industries faced redundancy and privatisation. In 1981, oppressive policing in poor neighbourhoods suffering the effects of a recession sparked riots, which were met with the appearance of long-shield riot officers in British cities. In Toxteth, Liverpool, CS gas was used for the first time on the British mainland against the civilian population. The deputy chief constable of Merseyside police who oversaw that groundbreakingly severe response was Peter Wright.

Given what is now known about Wright’s regime, the culture at South Yorkshire police and its culmination in disaster at Hillsborough in 1989, it is chilling to learn, from official papers released 30 years later, of the absolute backing the government gave him. This was an era before the Police and Criminal Evidence Act (Pace) came into force, coupled with the introduction of the Crown Prosecution Service (CPS) in 1986, to make decisions independent of the police, on the strength of evidence against accused people. That legislation was intended to address police malpractice – the framing or “fitting up” of people for crimes they did not commit, which had produced a series of miscarriages of justice through the 1970s and 80s, including those of the Guildford Four and Birmingham Six. But, in government papers released to the National Archives in Kew, Thatcher, her ministers and advisers can be seen determinedly seeking a tougher response from the police to the miners’ strike, with no concern for its implications.

On 14 March 1984, just a week into the strike, Thatcher explicitly referenced Saltley when told by MacGregor and Peter Walker, her energy minister, that pickets were preventing other miners from going to work. “The Prime Minister said she was deeply disturbed at these reports,” a note, by Andrew Turnbull, Thatcher’s private secretary, records. “The events at Saltley coke works were being repeated. It was vital that criminal law on picketing be upheld … It was essential to stiffen the resolve of chief constables to ensure that they fulfilled their duty to uphold the law. The police were now well paid and well equipped and individual forces had good arrangements for mutual support.”

Chief constables such as Wright had their resolve stiffened with prejudicial rhetoric, exemplified in a speech Walker made on 30 May, in which he described the strike as “a battle enthusiastically supported by Marxists to see whether or not the mob, using mob violence, can rule”. Walker praised “the courageous and tenacious action of the police”, which had, he said, saved the country from “violent mob rule”.

Not all chief constables approved this warlike portrayal of their duty to police an industrial dispute. Last year, after the Hillsborough verdicts, Sir Peter Fahy, the former chief constable of Greater Manchester police, lamented that a “them and us” culture had been created, from the tough policing of the 1981 riots through to the use of police as “an army of occupation” during the miners’ strike. Fahy said that this culture had also contributed to the failure to keep people safe at Hillsborough. At the time, in neighbouring West Yorkshire, Chief Constable Colin Sampson spoke publicly of the importance of preserving trust between police and mining communities for when the strike was over, declaring a “softly-softly” approach in which horses and riot shields would be used only as a last resort.

An injured miner being arrested at Orgreave. Photograph: Rex Features

After leaving the navy in 1954, Wright had been a policeman in Manchester for 25 years. In 1979, he joined Merseyside police, and in 1983 he was appointed chief constable of South Yorkshire police – a year before the mining communities inhabiting large areas of his patch went on strike. Wright seems to have fallen in line with the government’s generalisation of the miners as a hooligan mob, rather than people enduring great hardship in a campaign to preserve their industry. He embraced the conviction that he and his force were saving the country from anarchy.

It would be a year before the details of what happened at Orgreave would be analysed in court – a proper test of the government’s assertion that Wright had only been upholding the law. By then, the strike was over. Broke, exhausted, outmanoeuvred, overwhelmed and relentlessly vilified by the government and its media supporters, the miners went back to work after the NUM executive voted by a narrow majority on 3 March 1985 to call off the strike. It was and has always been hailed by the Conservative party as a great victory against the trade union opponents of commerce, but the returning men were walking into MacGregor’s mass closure programme and, ultimately, the sealing up of an industry.

Jan Freytag, a historian at the university of Bochum in Germany, found documents at Kew that show that days after the strike ended, on 27 March 1985, the government invited police chief constables to the Home Office for celebratory drinks.

The reception was explained in two notes to Thatcher. “Chief constables generally, and in particular those for Nottinghamshire and Yorkshire, made a very considerable contribution to resisting mob rule during the strike,” the first one said, “and you might think it appropriate to say so in person.”

Then, the day before the gathering, Thatcher was reminded: “You are looking in tomorrow … for half an hour at the drinks given by the home secretary for chief constables. The idea is for you and Mr Brittan to have an opportunity to say thank you for all the police did during the miners’ strike.”

On the list of those attending, from 14 different forces, were Peter Wright and Tony Clement from South Yorkshire police.

When the titanic strike by the National Union of Mineworkers (NUM) ended in defeat in March 1985, Britain’s media moved on to cover the Conservative government’s subsequent privatisations of nationalised industries, the stock market “big bang” and the rise of the “yuppie”. By the time the trial of the first 15 miners arrested at Orgreave and charged with riot began on 8 May 1985 at Sheffield crown court, little notice was taken – even though the police narrative completely collapsed at this point. In fact, until now, the trial and the extent of police malpractice alleged in court has never been prominently reported in detail.

Unlike the media, the accused miners had been unable to move on. Still on strike, their lives were placed on hold as they waited to see if they would be thrown in prison. All loyal union members, the men had gone to Orgreave from elsewhere in Yorkshire, and from the Nottinghamshire, south Wales, north-east and Scottish coalfields. They presented an unlikely collection of rioters. Three of them, David Bell, David Moore and Kevin Marshall, were young men. Most of the other 12 were married with children; the oldest, Bill Greenaway, from Blackwood in south Wales, was 51. All had spent their working lives in the hardest of occupations, underground or on the surface of coal mines. Bernard Jackson, 43, was a father of two teenagers, president of the NUM branch at Wath Main colliery in South Yorkshire, and the governor of two schools.

The full transcripts of the trial, in which the South Yorkshire police prosecution disintegrated, are now publicly available on the Orgreave Truth and Justice Campaign (OTJC) website.

It was opened by the prosecuting barrister, Brian Walsh QC, portraying the events at Orgreave as a sustained, vicious and unprovoked assault by miners on the police. In the witness box, Clement claimed that the conduct of the miners at Orgreave had been “the most serious disorder seen in this country this century” and that the police had responded reasonably. But he and the South Yorkshire police force’s version of events were to face an altogether less comfortable reception than at the congratulatory drinks with Margaret Thatcher.

Clement described mass ranks of “demonstrators” at the bottom of the field in front of the works before the lorries arrived to take the coke away. He said Scargill did a mock inspection of police lines at 8am, after which the police were subjected to a “terrific increase in violence”, a hail of stones, bottles, metal objects and bricks. As a defensive measure, Clement said he had sent horses into the miners at a walk, although he admitted that he gave no warning. Then from 10.20am, he said that he decided to clear the field to avoid a similar attack when the lorries arrived again, mounting a three-stage operation, advancing with horses, short-shield units, and officers with long shields behind. That pushed the miners up to a bridge that led to the edge of Orgreave village.

Clement said the miners had fought with a level of violence he had never seen in all his 33 years in the police force. Each of the men on trial was accused by two police officers, who had stated in mostly identical terms that they had seen him, within the context of a riot, throw stones. That could be enough to condemn the men, if convicted, to life in prison.

One of the trial’s many astounding elements is that the police had a camera close to the plant on the day, but the prosecution did not present the film in evidence. It was the accused miners and their lawyers who insisted on it being shown to the jury, against objections from the prosecution. According to Michael Mansfield QC, the film contradicted key aspects of the prosecution’s lurid description of events.

Police and miners clash at Orgreave. Photograph: Photofusion/Rex/Shutterstock

Mansfield, who represented three of the men, said it showed a generally orderly scene as miners arrived in the field in the sunshine, before massed ranks of police. Scargill did not perform a mock inspection of these lines at 8am; he did so much later, and it had not prompted violence. When the lorries went in at 8.10am, the miners made a short push against police lines, as if attempting to break through. Lasting for just 58 seconds, it was a standard ritual on picket lines that no miner expected to succeed. But immediately after that, the police lines parted and the horses charged. Then short-shield units and other police officers ran into the field and set about the men.

None of the miners denied that a small minority of people had thrown stones before the police charged. Mansfield even pointed out a group of around a dozen in the film, and challenged Clement as to why he had not sought to arrest them, rather than attacking miners in the crowd indiscriminately.

Clement defended the police actions as a reasonable response to a riot, and did not accept that they were at all excessive. He was accused of encouraging his officers to attack miners, because a senior officer could be heard on the film shouting into a megaphone: “Bodies not heads!” Clement argued this was not urging officers on with their truncheons, but merely reminding them not to use them on people’s heads.

This was when one of the miners, Russell Broomhead, was truncheoned repeatedly over the head, a scene filmed by news cameras behind the police lines. The officer who beat Broomhead was later interviewed under caution, although he was never disciplined. He said: “It’s not a case of me going off half-cock. The senior officers, supers [superintendents] and chief supers were there and getting stuck in too. They were encouraging the lads, and I think their attitude to the situation affected what we all did.”

In his book about the trial, The Battle for Orgreave, written with the journalist Tony Wardle, Bernard Jackson said that many miners were struck at random with truncheons at that time, on their heads and faces.

Jackson wrote that there was a lull after the lorries left: many miners had run away up towards Orgreave village, where there was an Asda; some stayed in the field, lounging in the sunshine. But then the police suddenly charged again, in the first of Clement’s three-part manoeuvre to clear the field, pushing them up to the bridge. The police horses and short-shield units chased the fleeing miners up to the road, Highfield Lane.

The only other escape was down an embankment across live railway lines, and hundreds of people did run across to escape the police charge. The missile-throwing from some miners after that – mostly over the bridge – was in defence, the lawyers argued, and a reaction to police brutality. None of the defendants admitted any wrongdoing or participation in violence. They had all been in that area and said that Police Support Unit (PSU) “snatch squads” were attacking people within easy reach or who did not run away, then arresting them. Their lawyers argued that there was a pattern in which these miners were fitted up with false evidence presented by two police officers.

Clement, asked about Broomhead, said that police had later gone to his home and found him working on his allotment – where he was arrested for riot. That prompted an outburst of disbelieving laughter from the accused men in the dock, who were warned by the Judge Gerald Coles QC to be quiet.

The barrister Peter Griffiths, representing James O’Brien – a Welsh miner who was shown in press photographs in the custody of police, bleeding down the right side of his face, torso and jeans from a gaping cut above his eye – put it to Clement that police officers over the bridge “went berserk” and lashed out at people at random. “If that happened, it is wrong,” Clement replied. “Officers should never go berserk. But I am not accepting they did.”

Yet as the prosecution moved on to the evidence against the individual men, it became apparent that all 15 defendants said the police had seriously assaulted them. Bill Greenaway’s wrist had been broken with a blow from a truncheon, David Bell’s leg was broken by, he said, a police officer kicking or stamping on it. David Moore said he was knocked to the ground, beaten, handcuffed, and then, when he was taken through the police lines, kicked and hit with truncheons.

Bernard Jackson’s account was that during the lull after the lorries had left, he had gone to the Asda to buy biscuits, then went and sat on a wall. He was unscrewing his flask to pour some tea when the PSUs charged. Ernie Barber, another of the defendants, 44 at the time, recalls it now and scoffs: “Bernard Jackson had a flask on him when he was arrested. Who takes a bloody flask to a riot?”

Jackson said that a police officer, unprovoked, smashed him in the face with a riot shield. He was then arrested, and nearly throttled with a truncheon.

“As I was dragged through the cordon, the coppers nearest lashed out with their truncheons,” Jackson wrote in his book. “‘Bastard miner,’ ‘Fucking Yorkie miner.’ Fists, boots or truncheons, it didn’t matter, so long as they could have a go at you.”

The South Yorkshire police force’s version of events had already begun to unravel under questioning. But when the arresting officers were called as witnesses to present their evidence against the individual miners, the full scale of alleged police malpractice became clear.

Cross-examination of the officers by the miners’ lawyers revealed that there had been an orchestrated operation by South Yorkshire police to dictate identical opening paragraphs for separate statements by dozens of different police officers. Furthermore, the evidence against the accused individuals was then shown to be unreliable, often contradicted by film or photographs of where they were – and there were to be worse embarrassments for some police witnesses.

The first of the accused to be considered was David Moore, who worked at Wath Main colliery with Jackson. According to Jackson’s book, Moore was “a fervent chapel-goer” from a religious family.

PC Fred Browning of the Merseyside PSU, which had been heavily involved in the charges over the bridge and arrests, told the court he had volunteered for miners’ strike duties because of the overtime, which paid an extra £300 per week. In court, he said that he had seen Moore throw a single missile at police. That contrasted with his written statement, in which he said he had seen Moore throw “a number of missiles”.

Challenged by the judge about this discrepancy, Browning replied: “I don’t know. I just put down that. Just the first thing that came to my head.”

At first, Browning said he had written the statement out on his own. Mansfield then read out the first four paragraphs. They did not relate to Moore at all, but were a general description of a riot taking place. They included this account: “As we stood there in the line, a continuous stream of missiles came from the pickets into the line. There were no shields being used at this time, and I saw a number of police officers were struck by these missiles.”

Asked about these paragraphs, Browning admitted that he had not witnessed “the bulk of that” himself. Then he acknowledged that 15 or 20 officers sitting at desks in police cabins set up at Orgreave “helped each other” to write these paragraphs. Pressed on whether these were his own words, Browning said: “Some of it is.”

Mansfield then read a list of other officers who had used identical words in their statements. Browning first said he did not know how that could be. Mansfield put to him that this account must have been dictated or written down for them to copy. Browning then admitted that a plainclothes detective, whom he said he did not know, dictated the first four paragraphs.

Mansfield confronted Browning with the fact that he could not have witnessed the events in those paragraphs, because he had not gone on active duty until 11.30am: “The truth is you weren’t there when no shields were being used, were you?”

“I can’t recall being there, no,” Browning replied.

“All you were doing was writing out what you were told, that’s right?”

“Yes,” he said.

Subsequent officers giving evidence denied at first that the introductory paragraphs had been dictated, but gradually it was established that they had. This had been planned in advance, on Peter Wright’s orders, to charge miners with the offence of riot, in which three or more people gather together with a common violent purpose.

Arthur Scargill being assisted by medics at Orgreave. Photograph: Manchester Daily Express/SSPL via Getty

Detectives from the South Yorkshire police serious crime squad, in plain clothes, were present at the command centre. Officers who had arrested miners would book them into custody, then go up to portable buildings to make their statements, where this introduction was dictated to them. It described the first element necessary for a conviction: that a riot was taking place. The individual miners were then accused, by two officers, of throwing stones in that context – ie, of participating violently in the riot.

“All of us believed this was a show trial, and the life term was going to be handed down,” says Arthur Critchlow, one of the defendants, who was 26 at the time and married with two young children. “It was extremely stressful for all of us and our families.”

Brian Moreland, from Durham, who had suffered severe stress awaiting the trial and whose marriage had broken down, was accused of throwing stones in identical statements by two officers. The statement made by one of the officers, PC Thomas Brophy, was handwritten, and the signature of the other, PC David Moore, was on it as a witness. Moreland’s barrister, Vera Baird, who is now the Northumbria police and crime commissioner, accused Brophy of having simply copied the second officer’s statement the following day, and then forging the witness signature on it. Both officers denied this, but Baird called for a handwriting expert to be appointed by the court.

Just before the expert’s report was due back, the prosecution suddenly offered to stop the whole case if the miners would accept being bound over to keep the peace. Although that would mean they would serve no jail time, they felt it would be accepting guilt. All 15 turned the offer down.

Critchlow explains: “It was the pure sense of injustice, that the police were lying. We unanimously refused the bind over, risking doing time.”

The prosecutor, Brian Walsh, then revealed the report of the handwriting expert, Richard Totty. He had concluded that the witness signature on Brophy’s statement, purporting to be that of PC Moore, was not written by Moore. It might have been written by Brophy, Totty said, although that was more difficult to determine.

Walsh then told the judge and jury that the prosecution was not proceeding against Moreland. There were roars of jubilation. Still, despite this scandal, the prosecutions pressed on against the other men.

In these cases – compiled before the 1986 Police and Criminal Evidence Act would require police interviews to be tape-recorded – many of the arresting officers included confessions from the miners in their statements or notes, along with admissions by the miners that their injuries had been self-inflicted.

Critchlow had been struck almost unconscious by a blow to the head, which had blood pouring from it. He would spend two weeks in hospital having his head drained of fluid, and experience continuing health problems, including double vision. PC Paul Norris, who arrested him, said in evidence that even in that condition, Critchlow had admitted throwing stones; that he had told the officer: “If Arthur Scargill says ‘Rush the police,’ I do. If he says ‘Throw stones,’ I do.”

Regarding the alleged naming of Scargill, Critchlow’s barrister ridiculed Norris in court, saying: “You might have had the first miner supergrass, mightn’t you?”

Both Norris and the other arresting officer, PC Robert Abson, explained Critchlow’s injury, saying he had been walking backwards, throwing stones, and tripped on a kerb and banged his head on a wall. George Foster, who also said a policeman hit him over the head with a truncheon, was stated by his arresting officer to have said at the time: “I got bricked by mistake by my friends.”

David Bell, a teenager at Orgreave, was said to have fully confessed to throwing stones by signing a police officer’s notebook, while lying in hospital under medication, having just had his broken leg put in plaster.

On the 47th day of the trial, which would be the last before the prosecution surrendered, the evidence against Ernie Barber was heard. Barber’s account, which his barrister, Marguerite Russell, put to the arresting officer, PC Gary Gray, was that he had not been doing anything wrong, so had not run away when the PSUs charged. An officer then smashed him across the face with a truncheon, and he crumpled into a thicket of nettles. Three police officers then set about him, beating him on the head and right arm, then a fourth arrived and beat him on the legs and feet. Barber was left with blood dripping down his face and body, but he was cleaned up for the police custody photograph – and the only injuries noted on the arrest record were nettle stings.

Gray, cross-examined by Russell, admitted that officers punched and pushed Barber, even though he had been offering no resistance. Russell put to Gray that the arresting officers at Orgreave, having had the introduction of their statements dictated, were simply told to say that the people arrested were throwing stones. He denied that. Asked to explain why he had said in his statement that Barber was throwing stones, when in court he said it was a single stone, Gray replied it had been “quite bad grammatically”.

Cole, the judge, made another rare intervention: “It is not a question of grammar, is it? … It is just inaccurate, isn’t it?”

“Yes, sir,” Gray replied.

The following day, Walsh rose and said the prosecution was withdrawing. The miners, described as a mob and “the enemy within” by the prime minister herself on national television, were acquitted.

Jackson’s book recalls the men’s joy and their resentment of the way that the police, the government and the media had behaved. “So that was it,” he wrote. “‘The worst case of public disorder this century.’ I wanted to get up into that witness box from which I had heard so much drivel spoken and tell the truth. I wanted to have my say. I felt completely and utterly cheated.”

After the trial collapsed, the defence barristers held a press conference. This was when Mansfield denounced the police evidence as “the biggest frame-up ever” and called for an inquiry. But compared to the overwhelming coverage of Orgreave a year earlier, reporting of the trial was scant.

The Thatcher government did not acknowledge that the Orgreave narrative had been reversed, or withdraw its support for South Yorkshire police – nor was it put under media pressure to do so. Home Office files seen by the Guardian show that Thatcher had prepared a statement supportive of the police, in which she would say: “I see no ground for a public inquiry.”

Government papers also show that Leon Brittan resisted calls for an inquiry into the policing of the miners’ strike arguing that it would turn into a “witch hunt” and be characterised by “anti-police bias”.

Free from outside pressure or scrutiny, Peter Wright did not accept responsibility for the trial’s collapse, or for the malpractice it had exposed. Neither he, for masterminding this operation, nor any individual officer, was ever held to account for anything related to it. In August 1985, Wright presented self-justifying explanations to his police committee, portraying the dictation of the introductory paragraphs as a matter of “assisting” officers from outside forces with “local knowledge and detail”.

“There was nothing sinister in this procedure,” he said.

Wright added that the “alleged forged signature” was being investigated. (Ultimately the director of public prosecutions accepted that there was evidence of perjury, but decided it was not in the public interest to prosecute.) The officer who truncheoned Broomhead was interviewed by South Yorkshire police on 20 June 1984, and the DPP advised on the same day that no charges should be brought. The Police Complaints Authority, the forerunner to the Independent Police Complaints Commission (IPCC), decided that no disciplinary charges should be brought against any officer.

In September 1986, South Yorkshire police produced its own internal report on the Orgreave prosecutions, titled “The Methodology of Evidence Gathering during the NUM Dispute”. It was compiled by the force’s assistant chief constable, Walter Jackson, for the deputy chief constable, Peter Hayes. Both these men still held those senior positions two-and-a-half years later, at the time of the Hillsborough disaster on 15 April 1989. Jackson was at the match, but not on duty. After Hillsborough, Peter Wright put Hayes in charge of gathering the evidence to make the South Yorkshire police case to the official inquiry by Lord Justice Taylor, and in subsequent legal proceedings, at which the force denied responsibility and blamed the fans.

Protesters in London last month calling for an inquiry into Orgreave. Photograph: Rob Pinney/LNP/Rex/Shutterstock

Jackson’s 1986 Orgreave report has still not been made public, but extracts were quoted by the IPCC in its 2015 review of the Orgreave scandals, which described it as “at best, self-justificatory”. The report does not appear to have accepted that there were any irregularities or malpractice in the police evidence at the Orgreave trial. No reform of Wright’s force was prompted.

“The report does not expressly address the issue of whether there was a conspiracy to pervert the course of justice,” the IPCC said in its 2015 review, “and so no reliance can be placed on it to dispel suspicions about there having been one.”

Thirty-nine miners then sued South Yorkshire police for assault, false arrest and malicious prosecution in a case brought by their solicitor, Raju Bhatt, based on the evidence presented at the trial.

The result was that the force, eventually, in 1991, settled the civil claims – paying a record £425,000 in compensation – to men it had accused of the century’s worst civil disorder. But it never admitted liability. The IPCC had access to the internal correspondence that led to the settlement. It showed that South Yorkshire police recognised that officers had committed assaults, and that there had been perjury at the trial, and that it settled because it did not want that to become public. The IPCC highlighted a note dated 29 June 1988, by Peter Metcalf, the solicitor advising the force on the civil claims. A police inspector had told him that film of Orgreave showed that officers’ evidence about Russell Broomhead had been wrong. Metcalf asked for a written report.

“But [the inspector] is rather reluctant to do this,” the note recorded, “because there would appear to be some opposition at [South Yorkshire police headquarters] to our providing evidence which could cause the case to be lost.”

Metcalf did not ask the inspector for a report. The IPCC commented: “The note … raises further doubts about the ethical standards and complicity of officers high up in the organisation.

“Withholding this information and failing to have the evidence of perjury and improper treatment investigated may, of itself, indicate that offences in relation to perverting the course of justice and/or misconduct in a public office may have been committed.”

Yet at the time, the force presented the settlement, publicly and even to its own police authority, as a means of reconciliation and moving on.

In April 1989, 54,000 people arrived in Sheffield to attend the FA Cup semi-final at Hillsborough. By then, as a succession of officers at the new inquests into the disaster testified, South Yorkshire police was a hardened, hierarchical force, ruled with an “iron fist” by Wright. Within that culture, the series of decisions that led to the deaths of 96 people began on 10 October 1988. That night, officers from F Division, which covered Hillsborough, played a prank on a probationary constable, posing as hooded armed robbers, luring him to an alleyway, terrifying him by holding guns to his head, pulling his trousers down and taking pictures of him, before unmasking themselves.

Many F Divison officers believe Wright overreacted to this episode because it was reported in the Sheffield Star and attracted the attention of local MPs. Wright took personal charge of a disciplinary procedure, and on 20 February 1989 sacked an inspector, a sergeant and two constables, demoted two more sergeants, and fined two other officers.

This remains a devastating reflection of Wright’s regime: not a single police officer was disciplined for the brutality at Orgreave, the alleged perjury and the failed “frame-up” that followed, nor for the horror that would descend on Hillsborough, or the lying and alleged cover-up after that. Yet Wright took severe action against eight officers for an internal prank that did not affect a single member of the public.

Disastrously, Wright then also moved the chief superintendent in charge of F Division, Brian Mole, a popular “gaffer” and nationally renowned football match commander who had extensive experience of policing Hillsborough. Mole was moved on 27 March, less than three weeks before the semi-final. Wright promoted in Mole’s place David Duckenfield, a disciplinarian who had never commanded a match at Hillsborough before. Wright said Duckenfield’s inexperience might be an advantage, because he would be “more on his mettle”. No senior officer questioned this decision; several testified that Wright’s orders were not to be debated.

In his evidence, 26 years later, Duckenfield admitted that he was grossly inexperienced, that he failed to prepare adequately for the semi-final, and that his failings at the match had caused the 96 deaths. Yet back in 1989, even as people were dying from horrific crush injuries, he lied, and said that Liverpool supporters had gained unauthorised entry through an exit gate, which in fact he had ordered to be opened, to relieve a crush he had allowed to build up outside. But in a 9am meeting on 16 April 1989, the morning after the disaster, Wright absolved his officers of responsibility and described the supporters as “animalistic”. Like his force’s immediate statements in 1984 that they had responded reasonably to a riot at Orgreave, Wright briefed this narrative of supporter misbehaviour to Thatcher and Sir Bernard Ingham later that day. In the legal proceedings, South Yorkshire police continued ruthlessly to make that case.

David Duckenfield arriving to give evidence at the Hillsborough inquest in 2015. Photograph: Dave Thompson/Getty Images

Peter Metcalf, the solicitor who was still advising the force on its response to the Orgreave civil claims, took on the Hillsborough case, too. He oversaw the process of officers’ statements being amended, removing crucial evidence about the police operation and criticism of senior officers.

Taylor, in his August 1989 report, saw through the police lies and determined that the principal cause of the deaths was police mismanagement. Government documents released to the Hillsborough Independent Panel in 2012 show that Thatcher toned down the response planned by her then home secretary, Douglas Hurd, to say that the government “welcomes unreservedly the broad thrust of the report”. Hurd also expected Wright to resign, although a home secretary could not call for him to do so.

Within No 10, remarkably, the police culture of denying blame and covering up was recognised. Carolyn Sinclair, an adviser in Thatcher’s policy unit, wrote of the Taylor report that the “defensive – and at times close to deceitful – behaviour by the senior officers in South Yorkshire sounds depressingly familiar. Too many senior policemen seem to lack the capacity or character to perceive and admit faults in their organisation.”

Yet despite so many people having died as a result of police failures, Thatcher responded by noting on a memo: “What do we mean by ‘welcoming the broad thrust of the report’? The broad thrust is devastating criticism of the police. Is that for us to welcome? Surely we welcome the thoroughness of the report and its recommendations.”

Wright did, in fact, offer to resign, but his police authority refused to accept it. He stayed on until 1990, having set in motion the force’s campaign to fight the Taylor report’s findings. At the first inquest into the deaths, South Yorkshire police blamed supporters again, and the jury returned the verdict, in March 1991, of accidental death. The families’ campaign for justice was concentrated on seeking accountability from those responsible for the deaths of their relatives and on overturning that inquest. They had to wait 21 years before it was finally quashed, after the HIP report of September 2012. Peter Wright died a year before that, in 2011, at the age of 82.

The verdicts of the jury at the new inquests last April – that the 96 people were unlawfully killed owing to the failures of South Yorkshire police and Duckenfield’s gross negligence – vindicated a 27-year fight to overturn the force’s lies. In January, two new criminal investigations into the disaster and the alleged cover-up sent files on 23 individuals and organisations to the CPS, to determine if any should be charged with offences including manslaughter, perjury and perverting the course of justice.

Margaret Aspinall, the chair of the Hillsborough Family Support Group, has become increasingly convinced that the roots of the disaster can be found at Orgreave, and the failure to hold South Yorkshire police to account afterwards.

“Ninety-six people died as a result of Orgreave,” she says. “This police force was brutal and corrupt, and if they had been brought to task after that, Hillsborough might not have happened. But my son and all those innocent people went to a football match and died horrible deaths, and we had to fight lies for so many years.”

* * *

The Guardian emphasised the connection between the events at Orgreave and the deaths at Hillsborough – which had previously been barely recognised – in April 2012. A BBC documentary in October 2012 then highlighted the dictation in the Orgreave statements. A month later, the South Yorkshire police force took the remarkable step of referring itself to the IPCC for possible brutality at Orgreave and malpractice in the evidence against the arrested miners.

In June 2015, the police watchdog produced a damning report, stating that it had found evidence of assault, a conspiracy to pervert the course of justice, perjury and a cover-up. Despite this, the IPCC decided that it could not undertake a new investigation, owing to the amount of time passed and the resources that would be required.

As home secretary, Theresa May received this report, and could, as expected, have left it alone. Instead, she invited submissions for a public inquiry from the Orgreave Truth and Justice Campaign. In the weeks following the Hillsborough verdicts, May and her current chief of staff, Nick Timothy, encouraged campaigners to believe that there would be an inquiry. In May 2016, she delivered her lecture to the Police Federation on the need for historic investigations to redress injustice. The same day, Timothy – who was at the time on a break from working for May – published his article on the Conservative Home website arguing strongly for an Orgreave inquiry.

Two months later, May was prime minister. But once she had arrived in No 10, her principled stance on the need to redress historical wrongs appeared to change – just as she transformed herself from a supporter of remaining in the EU to a zealous advocate of Brexit.

In July, Labour’s Andy Burnham challenged May’s newly appointed home secretary, Amber Rudd, about whether the commitment to an Orgreave inquiry was wavering. Rudd promised that the Orgreave question was “one of the most important issues in my in-tray”, and that she would read the OTJC submission, to which May, for all her bold speeches, had never actually responded.

On 13 September, Rudd met the OTJC, supportive Labour MPs including Burnham, and Margaret Aspinall. Arthur Critchlow was there, seeking government recognition 31 years on. They questioned whether Rudd had, in fact, read the submission and believed that she was ignorant of the basic facts. Nevertheless, two days later, the Times splashed on its front page that the government was indeed to hold an inquiry. The report cited Whitehall sources – believed to have included a close advisor to Rudd – saying the only question was what form an inquiry should take.

But the sudden, greater publicity given to the prospect of a Conservative government holding an inquiry into an episode that many in the party had mythologised as a great victory drew a fierce backlash, with critical articles in the Telegraph, Daily Mail and elsewhere. Lord Tebbit, Thatcher’s minister for trade and industry during the miners’ strike, was a prominent and particularly scathing opponent. Delivering the conventional, one-sided depiction of the period, he told the Times: “The only problem at Orgreave was that Scargill and his thugs held a mass, violent picket to stop people from going to work.” The police, Tebbit has said repeatedly, “behaved properly”.

A banner for the Orgreave Truth and Justice Campaign. Photograph: Dinendra Haria/Rex/Shutterstock

In common with most of those speaking out against an inquiry, Tebbit concentrated solely on the violent events of 18 June 1984 itself, not the allegations of perjury and perverting the course of justice in the subsequent collapsed trial. Speaking to the Guardian more recently, Tebbit said of the trial that it was “a cock-up”, and that he rejected the connection to Hillsborough, although he said he knew little about the disaster. “The only link with Hillsborough is that it involved the same police force,” he said.

This reaction seems to have worked on May, who was preoccupied with reassuring the party’s right wing of her commitment to Brexit. On 31 October, Rudd announced that there would be no inquiry at all.

“My view,” said Burnham, “is that it suited Theresa May’s political positioning as the home secretary to take on the police, and to seem like she was on the side of working people by considering an Orgreave inquiry. But after the Brexit referendum she became prime minister by doing a deal with the Tory right, and they regard Orgreave, against all the evidence, still as a sacred victory. When the Conservative rightwing backlash to an Orgreave inquiry came, Theresa May reverted to type. She showed that what she said about the need for historic inquiries, then on the steps of Downing Street, about addressing ‘burning injustice’, was empty rhetoric.”

Neither No 10 nor the Home Office was prepared to answer questions from the Guardian about how and why their stance on an Orgreave inquiry changed. Nick Timothy did not respond to requests for comment or an interview. Rudd herself turned an interview down. Freedom of information requests for the policy considerations leading to Rudd’s decision were refused by the Home Office, on the basis that advice to ministers is exempt.

The Home Office sent a stock response repeating the argument Rudd made in her statement to parliament, namely that “the policing landscape has changed fundamentally since 1984” and that “there would be very few lessons for the policing system today to be learned from any review of the events and practices of three decades ago”.

The Guardian asked No 10 if this means there has been a reversal of May’s policy as home secretary, that historic inquiries were “not archaeological excavations”, but “about ensuring justice is done”, and that “difficult truths, however unpalatable they may be, must be confronted head on”. Now, the passage of time was being presented as the very reason not to have an inquiry.

In November, when pressed by Yvette Cooper, chair of the home affairs select committee, Rudd admitted that in the 16 months between inviting a submission for an Orgreave inquiry in June 2015, and rejecting it in October, the Home Office did not consider the police files or trial transcripts – the actual facts of what happened. Instead, under May, then Rudd, they looked only at the original Thatcher government files from 1984 and 1985. It was after considering them, and what they revealed about that Conservative government’s actions, that they decided against an inquiry.

So Theresa May, who had lectured about the principled need for historic inquiries – at the same time as she argued for Britain to remain in the EU – reverted to the old nasty politics as she led the Brexit charge. She left intact Margaret Thatcher’s unconditional support for Peter Wright’s South Yorkshire police in 1985, and sealed the Orgreave scandal up again, like the coal still buried beneath Britain.

Main photograph: John Harris/Report Archive

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