Redknapp's was the latest in a series of show trials ? even if he had been guilty it could have been settled with a handshake

Now for 'Arry the Movie, a tale of fear and loathing in darkest Poole. It boasts a rags-to-riches hero ? Harry Redknapp ? along with Rosie his dog, a kindly Slav, Milan Mandaric, a villainous taxman and a Monte Carlo bank. Cheering from the terraces is a jury of 12 Londoners, good and true, who may know nothing of fiscal clawback but can tell a likely lad from an offside trap. With an uppity Italian leaving as head of the national soccer team, Redknapp's hour had come. Never did England's manifest destiny so beckon since Gordon left for Khartoum.

The taxpayer should be spitting with anger. Premier league soccer is awash in money, not just pay but bonuses, bungs, kickbacks and abuse of tax shelters. In the past 10 years I can find no one prosecuted or disciplined for them. The City of London police, undaunted and eager to retain their strange independence, decided to make a thing of a supposed fraud, at least of one they could understand. The force ignored the credit crunch and lifted not a finger against their financers, the banks ? but they have been fearless against horse-racing and soccer. It is like the Medell?n police force suddenly clamping down on food hygiene.

After failing to nail the jockey Kieren Fallon for race-fixing, the City police investigated football proprietors, managers, agents and players, including Redknapp's benefactor and co-defendant, the millionaire former Portsmouth chairman Mandaric. None of this had anything to do with the City, and all the trials failed at vast expense. Soccer, like racing, is wild west country, where witnesses do not talk. It is blessed and cursed by its public appeal and glamour, thanks to which heroes are judged by different standards to ordinary mortals and discipline poses a constant challenge to authority. So the police tried to get a couple of big fish for tax evasion.

Redknapp is a charismatic and successful coach. He has brought a dash of Cockney pride to a world dominated by foreigners with egos as big as their bank accounts. His talents have been rewarded by one club after another, culminating in the phenomenal revival of Tottenham Hotspur, now near the top of the league. But even Redknapp's fans gulped to learn of remuneration that has reached ?4m, and even "commission" for selling his own club's star players to rival teams.

They gulped too at the prosecution claim that, on declaring himself unhappy at being paid only 5%, taxable, on selling Peter Crouch from what was then his own club, Portsmouth, Redknapp's chairman, Mandaric, put ?186,000 in a secret Monaco bank account codenamed after his dog. Redknapp had himself described it as a bonus to a News of the World journalist, but the jury accepted his explanation at trial that he had been lying to the hack, and the money was in fact "seed money for investment", and therefore untaxable. In view of what he told the Sunday paper, it is easy to see why the revenue thought the case worth a punt.

The prosecution was characterised by ridiculously crude police methods. Dawn raids, ransacked offices, five-year investigations, expensive QCs and theatrical show trials seem aimed more at film rights than at common dignity. These methods yielded sympathy in court for Redknapp, and aided his ingenious defence that he was hopeless at money and "writes like a two-year-old". The process of prosecution eventually cost money out of all proportion to the sums at stake, reportedly ?8m. The law is the last realm of public service where concepts of cost-benefit are wholly unknown.

British justice has turned show trials into a blood sport, as most recently with the August riots, the petty charge for which Chris Huhne has been humiliated and now the Redknapp case. I am sure this is why Britain sends to jail more people than anywhere else in Europe. Had Redknapp been found guilty, he could have gone to jail for an offence that in most countries would have merited a quiet visit from the revenue and a cheque. Even in Britain, huge institutions reportedly get off their tax problems with a handshake over lunch. Yet working-class rioters went to prison for failing to pay for a pair of shoes.

I have served on three juries. For most members they are a baffling waste of time and money. Even for the under-employed middle-classes they are good for little more than a dinner party anecdote. None of mine was worth the expense, and in one case a gross injustice was done because the judge said, in effect, that one barrister made a rotten case. Highly paid professionals indulged themselves in archaic rituals at public expense, protected by "contempt of court" and "perverting the course of justice," offences against which incurred prison sentences.

Chief among these practices is that juries may not decide the relevance of the background history of witnesses. They are expected to grasp technical DNA evidence and the bias of paid "expert witnesses". They must disentangle complex financial law. Yet they must not know, or must disregard if they do know, anything that a barrister or judge has not told them.

This charade of ignorance is enforced even when surveys show that less than half of jurors have a clue what is going on. If hospitals were guided by such restrictive practices, surgeons would have us dead in droves. Some 90% of trials in Britain do not use juries. In most of Europe even big trials take place before judges and professional assessors, while sentencing is out of the public gaze in private. Britain's job-creation scheme for legal drama queens survives only because Lord Devlin declared it to be "the lamp that shows that freedom lives", and because so many MPs are barristers. They regard professional reform as something applicable only to doctors, academics and journalists. They launch constant inquiries into them, but curiously none into lawyers.

There may be cases where justice should be brought before the bar of public opinion, where it may turn on taste or proportionality in matters such as libel or national security. But modern trials either concern matters properly within the domain of local magistrates, or are so complex in their evidence as to require judges ? and assessors ? expert in law and science. Law, like war, is no longer for conscripts.

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