Most of the time, when two boats crash, the operators share fault. If you’re a passenger on either boat, you may have a personal injury case against the person driving the boat. If you’re the operator, you would only have legal recourse if the other boater had the majority share of fault under Washington law, which is 50% or more.
An exception would be a crash between a motorboat and a sailboat. Since sailboats are harder to steer, the law requires motorboats to stay out of a sailboat’s way. Though it’s not always true, operators of motorboats are more likely to be at fault in a crash involving a sailboat and a motorboat.