Thank you, sir.
Two of the categories are distinction without a difference. When you review the wording of subparagraphs 753(1)(a)(i) and 753(1)(a)(ii).... I have never encountered a case that would satisfy the wording of one yet not satisfy the wording of the other. Those two disjunctive tests are really a distinction without a difference. They both deal with patterns of behaviour, repetitive behaviour or persistent aggressive behaviour. They amount to the same thing in law in the cases I reviewed.
The third, subparagraph 753(1)(a)(iii), deals with brutal behaviour, and that is a test that is so high that I have never personally encountered it. Of course, it would likely be covered by the other two as well, although it could conceivably be a one-off situation.
The test in subparagraph 753(1)(b) is strictly dealing with sexual issues, so that is a distinction, although that quite often could blend in with either subparagraphs 753(1)(a)(i) or 753(1)(a)(ii) above it because it could be part of a pattern of repetitive behaviour or persistent aggressive behaviour, etc. The end result is you're dealing with risk posed by the offender, and the risk can be manifested in any number of ways. Every side deals with it.
I should pause to say this. The work I do with dangerous offenders is not adversarial. In fact, when I do the initial opening remarks, the trial crown is always there, and they sometimes look at me like I am the defence counsel because I insist on presenting everything to the court in an objective, dispassionate manner; the issues here are so important to the court, to the offender, and to society.