On Thursday 5 December 1991, Jack Trevor Story, one of my oldest and best friends, died suddenly of a heart attack. He was at his typewriter and had completed the revisions to his new novel Shabby Weddings, which he knew was his best since One Last Mad Embrace, that I considered to be his masterpiece. After 20 years, he said, he had found his bearings again.

I knew what he meant. Although he published some wonderful, quirky books during those years, including Letters to an Intimate Stranger, a collection of his Guardian columns, some of the most honest, funniest non-fiction a novelist ever wrote, he had never entirely recovered from what happened at Christmas 1969, when, after leaving my Ladbroke Grove flat, he and his friend Maggie MacDonald were arrested by the Notting Hill police.

Jack's work contains many references to that terrifying night. He frequently relived it. He had discovered at first hand what most black youths already knew, that the "basic decency" of the English police was little more than a reassuring myth. It was a singular irony of which Jack, the master of irony, was thoroughly aware.

He had always produced his novels from a considerable fund of working-class and lower-middle-class experience. Yet he had been content in his comedy thrillers and TV series (distinctive, clever scripts for Budgie, No Hiding Place and his own You're Only Young Twice) to portray the police as, at worst, bumbling incompetents. Since policemen were human beings, he reasoned, and since they were usually from similar backgrounds to his own (at 14, having failed to get a job as potboy at the big house, his first job was delivering meat for a Cambridge butcher), and since they spoke the same language, used the same pubs, had the same interests as most of his people, they must be as reasonable and ordinary as himself.

Jack's early work abounds with likeable coppers (his Spike Milligan film Postman's Knock, for instance, or Live Now, Pay Later), some of whom are almost as nice as his villains.

Though he never had any money, went bankrupt twice, lived mostly in bedsitters and was ambitious only for his craft, Jack described an England that was fundamentally benign. Socially, he took people on their own terms. He relished simple pleasures. He said true love wasn't actually about grand passions but about how you went round the supermarket together. He celebrated characters who were as amiably baffled in the corridors of power as he was (even though C P Snow had been an early mentor). His attitude towards authority was tolerantly amused. Courts, judges, tax inspectors, bailiffs and repo-men were, he had discovered, as inconsistent as everyone else and, though their reprimands, threats and exhortations puzzled and occasionally irritated him, he found they could do him no real harm and could be ignored like bad weather. He went on his way in spite of them, writing whatever was needed to pay his rent arrears or meet the payments on his car.

He never needed much nor expected much and he was frequently exploited. Hitchcock exploited him, paying him £150 for all rights of The Trouble With Harry; Bill Howard Baker exploited him, getting perfectly crafted gems of comedies for Sexton Blake Library at a discount; his publishers, especially the infamous Allison and Busby, ripped him off. Only the Manchester publisher Savoy stood by him through the hard times, recognising both his talent and his generosity.

I never blamed any of the women when they left him, for while Jack swam cheerfully at the centre of the maelstrom and had in those days a profound optimism, a sublime lack of anxiety about the future, for most his way of life was too uncertain. But nobody ever gave up on Jack easily. It was almost impossible not to like him. Radical feminists, determined to hate him, rarely failed to be charmed by him, for he had a way of taking everyone as equals. He never understood why people wanted power over others. He was proud of his vocation, dedicated to his art, selfish in its pursuit, but, of all the human beings I ever loved, he was one of the few almost entirely without malice or guile. In private or in the pages of the Guardian his agonies when Maggie left him were intense and he knew that his crazed efforts to win her back were driving her further away, yet I never heard a bad word about her or, indeed, any lover, any woman. Not a few, including daughters and ex-wives, continued to care for him, but he remained determinedly independent as a cat. He respected others' humanity, privacy and freedom as thoroughly as he protected his own. He had a singular delicacy, a courtesy that manifested itself in a rather old-fashioned reticence. To him the human spirit was sacred. He saw it manifested in the most unlikely places.

The minutiae of ordinary life provided for Jack the real clues to the mystery of the human condition. "Life," he wrote, "runs on such tiny points, like fat overstuffed sofas run on tiny castors." Abstractions, no matter how elegant, left him cold.

Jack's priorities were the same as his characters'—world war three might be starting or the biosphere about to collapse, but you had to make sure you got the tea on the table before your spouse came home from work. He observed, he recorded, he was naturally unjudgmental, and this led some to detect in him a weak social conscience. Yet one of his greatest heroes was the Orwell of Keep The Aspidistra Flying and Coming Up For Air. Another was Arnold Bennett. Another was William Saroyan. He admired authors who dignified the common, the vulgar and the mundane and could make of it something extraordinary.

I never knew a writer more willing to take on any job—pulp-thriller, movie, TV soap, newspaper column or experimental novel—and bring the same sense of integrity, of accuracy and truth to whatever he did. He never sold out. He gave every job his own stamp. You could turn on the TV and always recognise Jack Story dialogue. Sometimes his commercial work was so thoroughly and beautifully his own that those who commissioned it didn't quite know what to do with it. Frequently it was simply filed away and forgotten. His sporadic attempts at self-publicity, which were intended to improve his fortunes, were so blatantly inept, so impossibly bizarre and uncompromising, that they almost always failed. His TV appearances showed an affectionate eccentric with an almost infinite number of enthusiasms—for people, places, food, music, animals, literature. He always went too far in his own direction. He never got his contracts renewed.

Jack never blamed anyone else for his failures. To his friends and to him they were never failures. They were just something else he'd tried. He was incapable of sustained anger or even resentment. He envied no one their success, was always cheered when a good writer found a wider audience than his own. He had a strong sense of commonality and naturally identified his interests with society's. He was a genuine, unselfconscious egalitarian, as cheerfully tolerant of the Great and Pompous as he was of the Small and Meek.

After leaving my flat that Christmas, where we'd enjoyed a noisy orgy of guitar-playing—Jack was an ex-dance-band musician—and cocoa-drinking, interspersed with some serious draughts games, Jack and Maggie got into their battered old American car and, as far as I knew, set off home to their Hampstead bedsit. But the traffic lights were stuck on red at the Elgin Crescent intersection and, after waiting for some time, Jack decided to creep across. It was l am. Ladbroke Grove was deserted. As he moved slowly over the intersection, a police car appeared and stopped him. He explained the trouble. The policemen ignored him. Instead they asked him if the car was his. "Of course it's mine," said Jack, amiable as always.

"And that's your girlfriend, is it?" said one policeman, staring in. Taken aback, Jack asked what that had to do with them. "Isn't she a bit young for you?" he said. They told him they wanted him to take a Breathalyser. This was ridiculous, Jack said. He'd hardly had a drink all day. They became increasingly aggressive. Jack pointed out that they could now see for themselves that the light wasn't working.Tbey asked him for his driving licence. They asked again what an old man like him was doing with such a young girlfriend (Jack was around 50, Maggie still in her twenties). Jack said it was none of their business. Maggie, furious at their rudeness and innuendo, told them to bugger off. But then, Jack told me, things began to get increasingly surreal. The police informed Jack and Maggie they were under arrest and took them to Ladbroke Grove police station.

Jack, seriously asthmatic and suffering from claustrophobia, still couldn't take it very seriously but, as an asthma attack was developing, said he was leaving. They had his name and address. The police promptly grabbed him and began to push him around. Jack panicked. Then they performed the well-known local trick of stepping on his foot and pushing him heavily backwards, permanently damaging the tendons of his right foot. Maggie shouted at them to take their hands off him. She was also manhandled and dragged off to a cell. Jack was put in another cell. By now the asthma was worse. Jack begged the policeman on duty to have his inhaler brought in from his car. The policeman told him to fucking stop whining and threw a bowl of water in his face. After several hours, Jack and Maggie were charged with assault and Jack with drunk driving. They had not been allowed to make a phone call. Still confident that a court must surely set things straight, Jack was shocked when on perjured police evidence, he was found guilty. Later, on appeal, with a better prepared case and a good witness, the verdict was reversed. However, Jack was advised that prosecuting the police would waste his time and cost money he didn't have.

It's a familiar case, unremarkable to most of us raised in big cities, especially if we're black. I wrote to Jim Callaghan, then Home Secretary, to Leo Abse, then generally considered to be the conscience of the Labour Party, to other police officers at Ladbroke Grove, to the local papers, to the national papers and to Sir Robert Mark when he told us he was going to clean up the Met. In Notting Hill at that time we were familiar with this kind of behaviour and worse. Certain officers blatantly pursued vendettas against West Indians, and did more to polarise our community than even the invading gentry. Jack's misfortune was to seem working class, to have a woman friend younger than himself and a face which has been described as "lived in". He had assumed the Police to be ordinary, reasonable people. It was probably his most serious mistake, for by then the police were learning techniques of civilian control. They had new role models derived from TV cop-shows. They were heavy lads. PC Plod was assigned to school crossings and a Santa suit at the annual charity do. Jack had been misguided enough to believe that the police were more or less on the side of the angels.

Jack had a living to earn. After the appeal, he tried to get it out of his system in a political fantasy, The Wind In The Snotty Gobble Tree, which was serialised in New Worlds with dedications to the police in question. But the experience had profoundly changed Jack. His books—Morag's Flying Fortress, Little Dog's Day——were no longer about the ordinary vicissitudes of working class tally-men and pissed-off housewives—they were about corporate plots, international conspiracies, worlds where nothing was what it seemed.

Trying to get to grips with the trauma, Jack wrote a dozen novels, still unpublished. He had lost his old certainty in the fundamental decency of human nature and could not quite find anything to replace it. His working class and lower middle-class protagonists still interested themselves in life's minutiae, but they now existed in a world of threat. The majority of these books, though full of brilliant insights, wonderful language and extraordinary scenes, never fully came into focus. People thought Jack was being self-indulgent. He wasn't. He was trying for a technique which would help him make sense of his experience and it was still hard for him to stay angry. Hitler Needs You, the sequel to One Last Mad Embrace, was completed in the aftermath of his arrest.

Jack kept working. His Guardian column was axed. He published articles, reviews, did some TV work. For 20 years he went on producing novels, most of which are still unpublished. Thatcher's yuppies scared him. He couldn't begin to understand their priorities. He had grown up at a time when there was no shame in being poor. From somewhere he always managed to find hope. He knew that something in him had died and whatever was being born had not gestated completely. Then, at last, in August 1990, Jack had a serious psychological breakdown.

Pathetically terrified of authority, convinced that almost all his old friends and family were against him, he eventually escaped from Stoke Mandeville (where he should never have been) and for a short while lived rough. But he had a heart condition and carried no medicine. Eventually, in his own words, he gave himself up. Almost as soon as he took himself off the psychiatric drugs, he recovered. He never quite understood what had happened to him, but it seemed he had finally rid himself of that 20-year trauma. He began re-examining his literary and social roots, considering his old techniques, developing new ones and at last making clear sense of his experience.

Shabby Weddings, he said, was the best thing he'd written. But the memory of his Notting Hill Christmas remained and he continued to hold a deep suspicion of authority, fearful of any attempt to check his liberty. He told me that he felt if he made too much of his heart condition it would give the authorities another excuse to lock him up. I promised I would never let it happen to him.

I miss him deeply. My only consolation for his loss is that he died knowing he had written a masterpiece, that he had finally shaken off the ghosts of Christmas Past.

And that, Jack, is what I intend to celebrate this year. •