Sir: It is true that exposure rates of children are probably much lower nowadays, as suggested by Professor O'Carroll (letter, 3 August). However the next step in the argument about statistics on child safety is whether exposure rates have any bearing on the incidence of strangers murdering children.
It could be the case that the people who do these things are a tiny, but fairly constant, proportion of the general population. If these people experience a compulsion to abuse and murder children, then they will seek out their victims anyway. The only difference a lower exposure rate will make is in the ease with which they find their victims.
We need to be able to identify the people with these compulsions before they commit crimes - at which time there will still be public sympathy for them - and then find methods to restrain and change their abusive obsessions.