In a case dripping with nostalgia for anyone with a long memory and a taste for the quirks and trivia of British life, George Davis, a 69-year-old Londoner, has had a conviction for armed robbery, dating back more than half of his lifetime, quashed by the Court of Appeal. Mr Davis had been jailed for 20 years in 1975 for a raid the previous year on an office in Ilford, a case that gained extraordinary public attention because of the campaign to protest his innocence. While he languished in prison, his supporters – with his wife Rose in the vanguard – crashed a car into the gates of Buckingham Palace and draped banners over St Paul’s Cathedral to try to draw attention to his case. That having little effect, they went for the coup de grâce. With one day left of the cricket Test against Australia at Leeds and the contest finely balanced, protesters broke into the ground, gouged holes out of the pitch with knives and forks and poured a gallon of oil on to one end. The match had to be abandoned, costing England any chance of regaining the Ashes. It worked. Though some sections of public opinion were outraged, the words “George Davis Is Innocent OK” immediately turned into a national catchphrase and Scotland Yard announced, a little too hastily, that it was conducting an inquiry into the way the original case had been investigated. A year later Mr Davis was released by the home secretary. However, the wheels of justice grinding slower than even the dullest cricket match, it is only now that the case has been finally closed. And Lord Justice Hughes still said merely that the conviction, based on dubious identification evidence, was unsafe and that the court was not able positively to exonerate Mr Davis. Nonetheless, this improbable celebrity emerged from the court on Tuesday looking like an old-fashioned kind of jolly uncle – umbrella in hand, all beams. He kept most of his thoughts to himself, however, perhaps saving them for a Sunday paper. It was a case with multiple layers of irony, the most significant being that while Mr Davis was almost certainly innocent of the crime in question, he was not the most respectable gent in London. The year after he was released he was caught red-handed robbing a bank and got 15 years, reduced on appeal to 11. There were no protests. And Rose revealed at the time that among those angered by the ruin of the Test was the prisoner himself. With little else to do in his cell, he had been keenly following the match. In fact, it rained almost all day in Leeds anyway – and for the cricketers, if not for Mr Davis, the result would have been the same: a draw. There were, however, wider long-term consequences. Identification rules have been tightened, making it harder for police just to round up the usual subjects in these cases. Even more significantly, campaigners of every kind got the message. This was one of the earliest cases of its kind. Soon every group with a grievance – disgruntled fathers, environmentalists, Middle Eastern terrorists – grasped that a good stunt, be it minor or murderous, beats hours of patient argument. Peter Chappell, who was by his friend’s side again on Tuesday, was the spokesman for the campaign in 1975. “A man serving 20 years for a crime he did not commit is far more important than a game of cricket,” he said in 1975. Quite. But a spokesman for al-Qaeda would also say that the ends justify the means.