@agracier: Not to be pedantic, but their is no "conviction" in a civil trial. It would be a judgement in favor of the plaintiff.
A company is responsible for the actions of its employees while they're working. They also have an obligation to make sure their employees are aware of company policies and appropriate behavior in the workplace and to monitor it, to some extent.
That aside, the real issue is the company most likely has deeper pockets than the co-worker, along with insurance. Employers are *always* listed as defendants in sexual harassment cases. Even in a situation where there is no rationale (and in the US there would be a legitimate basis for suing a company for the actions of its employee), without a doubt, the plaintiff would list the company as a defendant and the case would be decided by "irrational people on juries who vote on emotions, not facts" and completely disregard judges instructions on what to consider and what not to consider.
While this is getting way off the subject of this thread, the "don't compliment a woman on the dress she's wearing" statement needs to be placed in context.
Let's put this in the typical situation. A man should not compliment women on what they're wearing unless he also compliments men. To do so could be considered a form of sexual harassment, as he is treating women differently than men. Yes, this may be a simple interpersonal interaction, but if the woman wants to file a claim, it would be against the company and the employee. So the general suggestion is not to talk about what people wear or how they look.
Of course in reality, that doesn't happen. I showed up to work last week sporting a haircut. Several people noted that it looked nice. No problem.
But it's a slippery slope, which becomes problematic when the comments are along the lines of "your butt looks really nice in those tight jeans," or a comment about cleveage. I'm not a fan of the fear of the "slippery slope" being used to prevent normal interactions, but this is the basis for these policies. There is no concern about crossing a line if you aren't on the field in the first place.