This might sound bad especially to you or the someone you know, but if the legal system (criminal or civil) was not able to act (presumably due to lack of evidence), then I don't think events or other organizations should act either.
The whole point is that the legal system is very slow, very hard to report to, and in some cases actively discourages assault / rape claims. CoCs can do better because they don't require as involved of a process
I'm not too worried about someone being banned from an event on hearsay, but I am very concerned about serial harassers
The former, while unfortunate, is not career ending. It just means they can't go back to that event. The latter scars many people and will likely cause some of them to leave tech. Also none of them will ever come back to that event.
I think that's covered by the CoC free case too. If there is or isn't a CoC and you convince the organizer that someone assaulted you, the organizer can and should ban them.
We do have different criteria for sufficient evidence for different consequences.
It makes sense to require something like 'beyond all doubt' to put someone behind bars for a few years.
It may make sense to have even stricter criteria (e.g. unanimous votes) to execute someone.
It makes sense to have lower criteria (e.g. 'preponderance of evidence') to impose a civil liability that takes all their money but does not put them in jail - there are cases of crime accusations where the level of evidence is so that were acquitted in the criminal court as the evidence was not sufficient for that, but the same evidence resulted in them being found responsible in civil court.
So it does also make sense to have a different (lower) standard of evidence and process to resolve CoC disputes, without bringing in all the heavyweight legal machinery designed for the high-stakes evaluation of whether someone's guilty of a felony. If the worst penalty that can be imposed is "our organization will consider you a baddy and won't deal with you ever again", then the accused does not need as much protection as if their life or liberty was at stake.
However, there still has to be some standard of evidence and at least some reasonable due process - in this particular case it seems that the bar has been set too low and this might need to be changed.
