[londons_explore]

As long as that speaker was one of many, I wouldnt have uninvited them.

If the audience has an issue with one speaker out of 10, they can take a lunch break then.

If it's one out of 2, I can see why they might not want to attend.

Using inclusion or exclusion to punish someone for past actions I would try to avoid at all costs. If someone has broken the law, the legal system is there to do punishment. It isn't your role as conference organiser/colleague/etc. to punish. You are not qualified to make decisions as to the veracity of the claim.

Perhaps the furthest I'd go is saying to them "you (rightly or wrongly) have a reputation for X. Please make sure none of that happens during the conference."

[village-idiot]

I feel that such policies fall apart when faced with truly toxic people. If the claims of the above article are true, I would consider the people being mentioned to be truly toxic.

[lawnchair_larry]

This is how adults should behave. And if people have a personal problem with the person existing at the conference (as in, this isn’t actually a violent person, and it’s an issue of discomfort as opposed to safety) that cannot be solved by avoiding them, then it’s probably those people who shouldn’t be there. Or anywhere else really.