The presumption of innocence, jake is a legal presumption, not a fact. It places the burden of proof upon the prosecution, not the defendant. And that is all it does.
When I last checked it was not the job of the police to undertake prosecutions. Since 1985 it has been the job of the CPS. The function of the police is to prevent crime, and if they cannot, then to identify and apprehend the perpetrators. In doing this they cannot be bound by this presumption of innocence. If they were they would be able to neither suspect nor arrest anybody. This is clearly nonsense (unless you�d like anarchy to prevail).
The police have limited resources, Vic, available to them to detect crime and they have to prioritise those resources. They know (from the figures accepted even by their senior managers, many of whom have been chosen for, shall we say, their complete impartiality, rather than any ability they may have as �thief takers�) that certain sections of the population commit a disproportionately high number of certain types of crime.
So when, for example, metal goes missing from my local church roof, there is no point, as part of their investigation, in the police stopping old ladies on their way home from the Women�s Institute. I would rather they have a nose round the nearest gypsy encampment first. That is what they do, and that is what I want them to do. If they turn up nothing, then move on to the old ladies.
If they need �educating� by the like of Ms Milani and her department to dissuade them from doing this, then they might as well pack up and go home. And if you cannot see this, then no amount of education from me or anybody else will persuade you otherwise.