Stan is sure of an Italian victory whereas Ollie is convinced that the trophy is destined for Paris.

You can't make your mind up either way. Cannavaro looks immoveable, but Henry is often irresistible. If ever a game was destined to end in a penalty shoot-out, then surely this is it. So there are three possible outcomes, Italy, France or a penalty shoot-out.

All possibilities have a theoretically equal chance of occurring, so the odds against each event happening is 2-1.

Stan is dispatched to the local bookie's office and told to put a tenner on each of the possible results. He arrives back clutching three dockets with the odds of 6-4 on each one. "Jaysus, that's a bit tightarsed, " complains Ollie, "I'd have given you 2-1 on the draw if you'd asked me."

Welcome to the world of betting exchanges, in concept an online facilitator of bar room bravado, but in reality one of the biggest issues to confront sports governance in generations. By betting traditionally, the boys in the Dog and Duck are paying a profit margin to the bookie.

The arrival of the exchanges has changed all this. For the cost of a relatively small transaction fee they have created betting markets that are global, pervasive and easily accessible. For every opinionated Stan, there is an Ollie somewhere who disagrees with him, and who is willing to lay his bet. As there is no profit margin for the bookie, the odds often tend to be better.

There is a problem though, and it nags like an enduring toothache. In betting exchanges you never know your adversary, they never really sit on the bar stool next to you and expound their views. With traditional bookies you know the enemy and their strategies but on exchanges you may be betting against a foe that has already determined the result.

For instance, what if that huge bet on the outcome of a football game was made with the referee or linesman?

This is the reality that crashed into the public consciousness and newspaper headlines this week. The integrity of horse racing is once again under microscopic scrutiny. On Monday morning at Bishopsgate Police Station in London, 'Operation Krypton' had offered up its first charges. Years of expensive investigations, hordes of police officers, hundreds of interviews and statements resulted in a dossier that allegedly contains 40,000 pages of incriminating evidence. Among others, three high-profile jockeys, Fergal Lynch, Darren Williams and Kieren Fallon, were charged with conspiracy to defraud customers of the Betfair betting exchange. In other words they are accused of acting illegally to profit from events over which they had control of the outcome. Betfair customers may well have been betting against the referee.

Although not a shred of evidence has yet been placed in the public domain, one tabloid valued the fraud at 100m.

Two conclusions were eagerly and greedily arrived at. The first is the predictable enough "sure everybody knows that racing is as bent as a four euro note, always has been". The second is a little more worrying, and seriously impacts on the reputation and livelihood of those charged. The three jockeys were immediately banned from riding in Britain while the charges remained open and were effectively deemed "guilty until proven innocent".

Are there chancers in racing? There is far more money in horse racing than in planning decisions and the tribunal industry has recorded how some of those temptations turned the heads, and morals, of many pillars of the community. However, the premise of the City of London police investigation is that corruption in racing is not just a minor virus infecting small time players, but a full blown disease ravaging the body of the sport in a systemic and destructive way. They contend that the spread of the disease has been helped by betting exchanges which make it profitable and easier than ever to 'stop' horses.

To paraphrase Anne Widdecome, British racing authorities have appeared to believe for a long time that "there is something of the night" about Kieren Fallon. While Fallon was reportedly 'shocked' by the charges there were many others who were not. More than any other sportsman he carries with him an audacious air of daring and danger that seems to invite controversy and scrutiny, but the attention of the authorities just seems to make him better at his job.

The others caught up in the investigation are not as fortunate. They have neither the resources enjoyed by Fallon nor the same kind of ice water flowing through their veins.

Since the police began investigating Darren Williams two years ago the number of his mounts and winners have plummeted. He described last week's charges as a "bolt from the blue", and continued that "without doubt the arrest has affected the number of rides I am getting".

It is a similar story for Lynch. Over the last number of years his total winners have dropped from 100 in a season to just 22 this season. Much of this is attributable to the finger of suspicion that has been mercilessly pointed in his direction.

The authorities in Britain are confident that they have a reasonable case. They point to their dossier with the same kind of smug, puffed-up certainty with which George Bush and Tony Blair announced that they had incontrovertible evidence of Saddam's weapons of mass destruction.

During the investigation a police officer reportedly asked Fallon if pulling on the reins slows down a horse. They would look silly if they closed a multi-million pound investigation without laying a charge, but downright stupid if their case is not built on firmer foundations than this.

Fallon clearly thought likewise when releasing a statement on Friday. "I cannot understand this decision as I am confident that I have done nothing wrong, and my lawyers are confident that the case against me has no validity whatsoever. In fact, I am utterly amazed the police were able to charge me based on the evidence I have seen.

"Unless my suspension is lifted my career is in ruins. . .

My livelihood is dependent on racing and I will be appealing against this decision as it is extremely harsh and inconsistent, given the HRA [Horseracing Regulatory Authority]'s verdict on Alan Berry published earlier this week."

In the meantime there was more bad news for the accused jockeys on Friday when their appeal to resume riding in Britain ahead of the court case was not allowed.

It will be at least 2007 before any trial takes place and they are still innocent despite the tabloid-driven scandal and innuendo. The probability of an eventual conviction is anybody's guess. Back in the pub, Stan is fairly dismissive and is offering 12-1 against any guilty verdicts. Ollie is a little more cynical and uncertain and will only go 5-2. The betting exchanges have not yet created a market on the outcome. If they do, we all better hope that the members of the jury don't like a bet.