Not all murderers boast about what they are going to do, not all show signs of their twisted minds, I'm afraid the only way to study & understand is at the expense of their victims,
I quite clearly explained about the do gooders who allow through their study & understanding which goes quite some way in the release of these objects!
If you read through the board you will see the poster who said these things & it's clearly publicised about such cases.
I can't quote you I haven't the capabilities on this equipment, I rely on reading back!.
In an ideal world we would be able to spot these misfits, we neither live in an ideal world nor do we have enough knowledge of the human mind nor the capabilities to fathom the criminally insane, no amount of study & understanding will prevent other like minded people from achieving their goal!!