Lucy Letby: Difference between revisions

Emotions are already aggravated; the stakes are raised yet higher by the undoubted loss and grief of the families of lost infants. That grief cannot be avoided. It burdens the families whatever  its cause. ''That'' the families are bereaved is not at issue: the question is ''why'': neither conviction nor acquittal necessarily delivers or denies justice for their loss. One can respect the families’ unimaginable grief and seek to ameliorate it, by arguing her case.  

These murder cases have an unusually wide range of unknowns. In isolation , we cannot say whether there was any murder at all. The deaths could have been innocent, and they could have been culpable to some legal standard short of murder (negligence, for example), and that culpability may be someone other than Lucy Letby. As the [[Post Office Horizon IT scandal]] has illustrated, striking misadventure can emerge from the collected actions of many mediocre people, none of whom had in mind any great malice. Crowds can act with delusion and madness, just as they can with wisdom.

Where there are unknowns we talk in terms of ''probabilities''. What are the odds that this could happen by chance? What are the odds that the same thing could happen ''repeatedly''? For there is kind of meta-statistics at play here, too: even if the odds are fair for an individual case, an unusual repetition of cases creates its own meta-narrative. It rebuts the individual presumption.

Roll once and get a six, and there is no surprise. This will happen one time in six, and ''there was no more likely outcome''. Rolling a one or three is just as surprising.

Rolling three consecutive sixes is less probable, but still not infeasible: you would expect it to hby chance once in two hundred and sixteen sequences. If you are managing tend of thousands of sequences, you should be surprised if there are not several instances of three consecutive sixes.

But the odds of rolling ''fifteen'' consecutive sixes are a shade better than one in half a trillion. You should start inspecting your die. It is far, far more likely that that the die is defective. (If you manufactured a half trillion dice, would not one of them be malformed?)

This is the essence of the “shift pattern” evidence against Lucy Letby. Being premature neonatal infants and kept in hospital, these are children at heightened risk of “natural” death: that is why they are in hospital. The number of deaths per annum varies by year, but it is greater than zero. Let us say there are one thousand patients in a year, and on average five of them die. The probability of a given infant dying — where we have no prior information that infant — is therefore 5/1000 or 1/200.

 

 

 

 

: while each of the events on her shifts was in itself explainable, the sheer number of consecutive deaths on her shift were not.