a post over here at Talking Philosophy, and it's attracting some good, thoughtful discussion - although the comments thread is fairly brief at this point.
As I say in my latest comment on the thread, you'd hope that what convention organisers are really trying to do is create an environment that won’t be hostile or demeaning to women (or, presumably, anyone else, but I do think that particular issues arise with making the environments of conventions welcoming to women).
Perhaps policies should say that explicitly – it's vague, but it would have some meaning in that it could govern how the rest of the policy is interpreted. Instead, the policy that I'm criticising in the post has prohibited all sorts of categories of behaviour that are described in sufficiently sweeping terms to (one hopes inadvertently) catch up innocuous or beneficial behaviours, such as selling posters of pre-Raphaelite art.
Of course, what is hostile or demeaning to women (and others) is also contestable, and there are large grey areas. We’ve discussed some of the issues right here at this blog, where I’ve often complained about demeaning representations of women in comics. What is perceived as demeaning will depend on certain cultural codes, and not everyone has internalised the same codes in their heads. There are no answers that are objectively binding - there is no such thing as an objectively demeaning image in, say, a metaethicist's strong sense of "objective" - but there certainly are facts about what will, in a particular society, strike ordinary, reasonable people who are not especially prudish as demeaning to women. We're looking for images that are objectively demeaning in the weak sense of "objective" used by lawyers - i.e. not what a particular person actually experiences as demeaning but what an ordinary, reasonable person within the milieu would probably perceive that way.
However, the main thing that a convention needs to do is make clear that no harassment of any kind will be tolerated. I.e., if someone hassles you - sexually or otherwise - the organisers will have your back (Richard Carrier put it that way in one of his posts on the subject, and I think it's as good a way to convey the idea as any). You need the policy to specify how a complaint can be made, and everyone needs to know that complaints will be investigated fairly. No long list of specific prohibited behaviours is needed. People generally know when they are behaving in nasty or callous ways. The point is to make clear to the small minority who do so that it won't be accepted (and to give that sort of reassurance to possible victims).
There's more from me in the comments on the thread at TP.