You begin to feel strangely sorry for the Portuguese police. A golden-haired little girl was left untended while her parents dined. She had vanished when they came back: every mum and dad's nightmare. But this particular mum had fantastic cheekbones, and dad was a top doctor, too. They were articulate, photogenic, resourceful and desperate. They resolved to let waves of their anguish roll across Europe in the hope that someone would spot their daughter. And the press, of course, rolled in.
Now, blame games come easy. If you want to blame the tabloids, the broadsheets and a three-ring circus of TV crews, then be my guest. Anyone who scanned this paper's Saturday compote of Fleet Street front pages - from "Give back our Maddy" through "Suspect behaved just like Huntley" and "We can prove parents did it" to "Police case falls apart", over five torrid, circulation-sustaining months - has all the ammunition you could need. Too much gory gossip, heedless speculation and simple sensation on all sides. But shooting the messenger is only a sliver of this story.
Headlines, in the marketplace of human interest, mean that millions of human beings are following each twist and turn; and paying good money to do so. We're all part of the equation. Our pennies turn up the heat under Portimao police headquarters, too. Our preconceived notions and prejudices drop into a pattern. They dealt in "smears, slander and dirty tricks". Well, what did you expect? The police are foreigners, aren't they?
"The way it works is that we can't get official police comments, so we have to rely on tip-offs from them. We know they use us at times ... as they did when they drip-fed us snippets that might exert pressure on the McCanns to confess," a local freelance tells the Sunday Telegraph. So there you have it. One cop or another spilling supposed beans on alleged toast to any reporter who'll buy him a cup of coffee. A swill of garbage heading straight into print.
But pause, because high horses are standard issue here. You'll probably remember how young Euan Blair got plastered in Leicester Square, then found himself plastered across front pages. Why? Because one of Scotland Yard's finest picked up the phone to a newspaper mate, and got more than baked beans for his pains.
You'll certainly remember the torrent of leaks that lapped around Downing Street through the cash-for-peerages business. You'll remember the extraordinary flow of subterranean briefings that accompanied the hunt for Jill Dando's killer (a conviction once more under review). And, because it dropped out of sight just as the McCanns achieved maximum salience this month, you may also remember Michael Barrymore.
Six-and-a-half years ago, Barrymore and a couple of friends underwent trial by headline after a 31-year-old man was found dead in Barrymore's swimming pool. There was too much evidence of booze, ecstasy, coke and sex around. One conclusion led to another. Maybe the inquest on Stuart Lubbock recorded an open verdict. Maybe Barrymore was cautioned but left uncharged. In any case, he was gay, wasn't he - and out of control since his wife had left him? In any case, his TV and stage career were kaput. Goodbye £2.5m a year, hello bankruptcy. And hello again to the whole affair this June, when Essex police - case reopened - suddenly arrested him on suspicion of murder.
Yet scroll forward until the start of this month, and what do I find? The Crown Prosecution Service deciding that the cops had provided no basis to bring criminal charges, that Barrymore was innocent OK in every relevant legal sense, that those six-and-a-half years of charge, counter-charge and ruination had led to nothing. "We are disappointed that our latest inquiries have not brought us the answers the police and Stuart's family were looking for and we remain committed to finding out the truth of what happened that night," says the cop in charge doggedly. No justice is done.
And the linking thread to all these affairs, with a side-strand for Portimao, is sheer weight of publicity. In its glare, police forces anywhere in the world, that may be admirable day by day, buckle under the strain.
Remember, finally, how Colorado police failed so utterly to find the murderer of JonBenet Ramsey, the toddler beauty queen discovered dead in her parents' basement in Boulder; how DNA evidence went astray; how John and Patsy Ramsey endured years of suspicion to no avail. There's nothing "foreign" about this experience. From Portugal to America to Essex, the searchlights reveal the same sad thing. Forget CSI or Silent Witness. Anywhere you look, policing is as frail as Jean Charles de Menezes' last moments. And the damnable thing is that when Gerry and Kate McCann went so public, they in part ordained what happened next.
Peter Preston