DNA revisited again
.In recent weeks my articles DNA revisited - part 1, DNA revisited - part 2, and DNA samples from everyone?, have dealt with concerns about the extension of the DNA database. The recent McCann saga illustrates how DNA evidence is far from straightforward. (Although this is a case with no database implications as regards the family itself, since this is Portugal not here and the family would be obvious people to ask for DNA irrespective of it already being on the database).
One difficulty is that no one has the faintest idea what this DNA evidence is or what it purports to show. It is likely however that any DNA evidence will be far from conclusive.
Any lawyer will know you wait to see what the evidence is and what the explanation is before hazarding a view as to whether there is case to answer. Notwithstanding that, there are it must be said some bizarre aspects to what seems to be the alleged case against the McCanns. Firstly, the allegation seems to be that a parent could accidentally kill a child and then immediately (with the connivance of the spouse) launch upon a careful cover-up campaign. There are monsters who deliberately kill their children, and I suppose it is conceivable that such a person would be able to carefully and unemotionally plan their response, but I confess I find it difficult to see how any parent could have accidentally killed a child and then be sufficiently composed to launch upon an immediate cover-up. Had they done so, one might have expected that with the police apparently going nowhere with the investigation they would have avoided publicity and any criticism of the police, knowing that in those circumstances the police investigation would be more likely to grind to a halt. The McCanns did the precise opposite. Given the high profile campaign and the plethora of media interest, it is difficult to see how they could have hidden and then disposed of a body, even supposing that they were mad enough to stimulate media interest whilst they had a body to dispose of.
Two more features of the supposed case stand out. One is that the police regard as suspicious the conflicting accounts of what happened that night from the various persons at the dinner party. This was a group of professional people on holiday, having dinner and drinking vast quantities of wine. You will all have been at similar dinners. At such a dinner there would be little chance of anyone having a good grasp of precisely what occurred, and in what sequence, and who said what. It would have been suspicious if the accounts tally precisely. Likewise I do not see the relevance of the suggestion that there are clues in the diary of Mrs McCann that she struggled to deal with the children. I would like to know which caring parent has not, or who has not expressed themselves in intemperate terms at times. I for one have openly said a number of times that I felt like strangling one of my children, but it was never meant literally or seriously, I would never really have harmed them (nor did I!),nor did the people I spoke to ever take the comment as indicative of anything other than loving exasperation. If these are seriously regarded as compelling circumstances (and even allowing for the fact that one has no real knowledge of what the true state of the evidence is) it does not say much for the cogency of the case against them.
All will no doubt be revealed in due course. If however the view taken is that there is simply no substance to the case against the McCanns, it does raise the question of what view was taken of this DNA evidence and why. Forensic evidence is evidence which has to be tested like any other. It is too easy just to regard it as proof positive. Although it may become more sophisticated, in many cases there will be large issues as regards how one interprets a DNA match and as to the probability of a false match occurring. DNA evidence is a valuable tool in the fight against crime, but it should never be the be all and end all.