I’m not familiar with comparative fault. What is that?
This varies from state to state. It should be discussed with your insurance agent so they can explain how, and if, it applies to the state where you live. Under compartive fault law, insurers are allowed to investigate an accident and make a decision as to the percentage of fault of all parties involved. They will make voluntary offers based on this opinion. If you disagree with their evaluation, you should consult an attorney or turn over the matter to your own insurance company to handle under your collision coverage.