I focus on the good they have to tell about their God and if they broke the law of their God, they should take it with him.
How much good do you think outweighs the death of a child?
I don't know of any JW I met who been accused of raping someone.
Relatively few JWs are rapists, but many (most?) promote and defend a church structure that allows rapists to be shielded from the consequences of their actions.
The rapists themselves are more directly responsible, but the church membership as a whole shares in the blame.
Ask these JWs you know what should happen when they suspect that they think their child has been abused by a church member. I would bet good money that a significant percentage would say that they wouldn't go to the police.
More to the point: when a JW comes to your door to invite you into their church, regardless of their personal feelings on rape, they are working to promote and expand an organization where rapists and other criminals often get protected from punishment. This fact ought to be considered when evaluating the ethics of proselytizing for that religion.
Do defend their right to be religious, yes I do, do I agree with everything they say or do?. no, I don't, but that does not mean i need to treat them badly.
It's not about disagreement; it's about harm. If a negative reaction from me makes a proselytizer for a harmful religion stop and reflect on whether they're being a force for good, then I've done something positive.