The previous one was, loosely speaking, a sociological observation. This one is philosophical.
Whatever else may explain the extraordinary level of interest there now is in what really happened to Madeleine McCann, the case highlights as dramatically as any could why truth matters. In doing so, it shows what a lot of useless claptrap postmodernism is. For, while (as I've said) I don't know what the truth of this particular case is, one thing that's clear to everyone is that there is a truth about it: something really happened, an event took place involving Madeleine, and what it was is quite independent of what people now say - whether 'yea' or 'nay' or 'this' or 'the other' - about what they think happened. Apart from anything else, the event pre-existed all the different contemporary 'discourses' about it. In other words, there's a reality of the case, and the opinions, judgements, hunches, might be right or they might be wrong, and it matters, desperately, which of them is right. Discursive construction, interpretation, might be free, but not every account of what happened is as good as every other, and the better accounts are better because of something out there - that is to say, beyond the accounts themselves.
So much for claims of the sort that there are no pre-discursive realities, that everything is mediated via the language or theory in which we try to grasp it, and that the idea of an account of something corresponding (or not) with the thing of which it is an account is a useless metaphor. Even the weaker claim which concedes that there are these realities, but says we can't 'get at' them because we are imprisoned within our conceptual schemes, linguistic distinctions and so forth, can't be sustained. We have observational practices, means of collecting evidence and means of checking it, that do precisely put us in touch with the reality we're trying to ascertain. It starts with looking.
Or else what happened to Madeleine McCann is no more than the subject of alternative viewpoints - and so is every other crime, of whatever magnitude. If there is no truth, there is no crime. There are only different stories.