I will start off, and then Tim...and I see that Mark had his hand on the microphone.
Very quickly, the challenging part in this is the spectrum of activity that gets the person to actually commit the act. It's a little bit like the radicalization aspect. It's not illegal to be radicalized. It's when you get to the point that you're committing that criminal offence that it becomes an offence.
It is difficult to really identify when the individual will commit that act. That is a challenge. There's a spectrum of activity, and identifying that single point, what triggers that person to do it, is sometimes difficult.
I will pass it over to Mark, who would like to add something.