Every state runs its car accident claims through one of two basic legal systems: tort, or no-fault. Which one your state uses affects who pays first after an accident, and whether you can sue for pain and suffering.
Under a tort system, the driver found at fault in an accident (through their insurer) is responsible for the other party's medical bills, property damage, lost wages, and pain and suffering. Most states use this system. A handful of states — Kentucky, New Jersey and Pennsylvania — let drivers choose between full-tort and limited-tort coverage: limited tort gives up the right to sue for pain and suffering in exchange for a lower premium, while full tort keeps that right at a higher cost. Check your state's current default and options directly with your insurer, since these choice rules can change.
A no-fault system requires your own insurer to pay your medical bills after an accident regardless of who caused it, so injured drivers get treatment without waiting on a fault determination or a lawsuit. In practice, U.S. no-fault systems are really a hybrid with limited-tort rules layered on top — you still may be able to sue the at-fault driver for serious injuries, just not for the smaller claims your no-fault coverage already handles. The core no-fault benefit is usually personal injury protection (PIP), which covers medical costs for you and your passengers no matter who was at fault. A few states layer additional no-fault benefits on top — for example, New York offers an optional extra benefit (Optional Basic Economic Loss, or OBEL) covering further lost income and related costs beyond the standard PIP amount.
Many accidents aren't 100% one driver's fault, which is where comparative negligence comes in. It lets each side recover a share of their losses reduced by their own percentage of fault, rather than an all-or-nothing outcome. There are two common versions:
Which version applies, and exactly where the threshold sits, is set state by state, so it's worth checking your own state's rule (or asking your insurer or an attorney) if you're ever in a shared-fault accident.
AutoInsuranceQuery editorial team. Last reviewed: September 16, 2026.