I'm currently working on an article that addresses the issue. Without giving legal advice and summarizing briefly and generally: Homeowners or renters insurance generally covers liability claims. There are a handfull of exclusions that might come into play in a dive situation: (1) business pursuits, (2) professional services, (3) watercraft, (4) family members, and (5) intentional acts. If the claim arises out one of these, it will probably not be covered. There is, of course, the question of what arises out of what. Beyond that, liabilities may well be covered, especially things like dropping a weight on someone's foot, etc. Stay tuned for the article.