I suspect it's more of an underwriting question than a rating question i.e. an accept/deny coverage based on the answer vs. add premium. In order to charge rate they have to file the rate with the State Division of Insurance but I'm sure if they could run numbers to justify gun ownership as a rating factor if they wanted to. For example, in MA & many other places, no matter how legit the shooting is you're getting arrested (not covered because that would be a criminal act) and also sued in civil court, which would then bring the insurance carrier into it. Even if they end up denying a claim or you win the lawsuit, the insurance carrier will incur significant legal costs involved determining coverage/defending a civil case so it shouldn't be too hard to come up with some sort of rating rationale. The pro 2A community likes to talk about the number of times firearms are used for legitimate defensive purposes, and if most of those still end up with the shooter getting sued in civil court by the perp... you do the math. Insurers don't care about fault, they care about claims/costs. You can be the most righteous person in the world, but if they're incurring large costs defending you or settling claims, eventually they're not going to want to do that anymore. Things like fire/wind etc. are FAR easier to run the numbers on that liability issues.