No, it's not my fault when I make a 10mph turn and someone pretty much walks into my fender.
Self righteous thinking will buy you a trial with potentially an excess verdict. Maybe criminally you are not at fault, but civilly you can be at partial fault. Say a jury finds you 10% at fault and they award 2 million in damages - guess what, you are on the hook for $150,000.00. Or, you can admit your guilt, the insurance company can tender the policy, and you are free and clear of an excess judgment. It's your call.