I guess this is where the market comes in handy. Assuming everything would be better and safer in a libertarian society, this question is laughable. But for sport…
We have to assume, like I said, that a contractual society would have logical, righteous, protections for situations like this. But you can always take a risk and jump in. If someone felt their rights were violated they would be justified in retaliating or prosecuting—though they wouldn’t be obligated to.