I saw an interesting perspective on this from a healthcare professional today on Reddit, where there is a long thread on the subject (https://www.reddit.com/r/LucyLetbyTrials/comments/1r114xb/if_letby_is_innocent_why_does_she_never_insist/)
So I think one of the more significant oversights by the police was not appreciating the sheer enormity of everything that had happened to her prior to her first arrest, as well as the fact that with suspected health care killers, a completely different set of rules apply.
Mere hours before the start of a night shift, she was called and asked not to come in to work, after which she never returned to clinical duties. That’s how her removal was initiated, very abruptly. It is exceptionally unusual to be removed from clinical duties like that, exceptionally unusual to be removed from clinical duties at all. Normally any disciplinary action puts the absolute fear of god into healthcare workers. But to be removed from work because some of your colleagues think you may (in whatever way) be responsible for the deaths of babies you’ve care for, would be an unimaginably hellish experience.
She’d been deep into this kafkaesque nightmare for two solid years before the police came knocking. But the thing is, I don’t think she was ever sure that she hadn’t done something wrong, that’s a very, very normal response for a healthcare worker. That’s the fundamental difference between letby and any regular murder suspect, she very much had been involved in the deaths of these babies (well, the evidence that she was involved prior to the cardiac arrest for two of the infants is dubious), as had many others on the unit. Unlike a regular innocent suspect, she can’t completely distance herself from these deaths. An open mind that maybe she did do something wrong, after all, the establishment certainly seems so think so, is entirely normal.
I’ve attended coroners court on only one occasion. I was very junior, and I was very nervous, struggling sometimes to answer straightforward questions, nothing accusatory, the coroner was very congenial. If he’d become more pointed I would probably have crumbled, even though I really hadn’t done anything wrong, at the time I wasn’t so sure of that.
This is all relevant, as I think the police failed to recognise what they were dealing with, and we saw that in the documentary. A look of shame, or dejection, speaking in hushed tones, none of it is suggestive of guilt in the same way that it might in regular murder cases.
The prosecution barrister even went after her about texts she sent that she was having a mini meltdown after being told to not come into work at short notice. Highly highly unusual practice, and I think many of us would freak out if the same thing happened.