Go to this site and read.
This is important.
I've read the arguments that a con shouldn't have to have a specific policy spelling out that it's wrong to grope a woman, that it's already against the law and should be common sense, but unfortunately some fans (and it's a small fraction) don't have that common sense. It's like a company has anti-harassment policies in its human resource policies. It just makes good sense that a con has something spelled out and some sort of policy to follow when someone has a complaint.
Cons are supposed to be fun and no one should have to worry about things like this.