Comparative negligence is applied in three slightly different ways, depending on the state where the accident occurred. The more generous states allow you to recover compensation for your injuries in an amount based on the other person's fault no matter how great your own fault was. Most states, however, use a slightly more restrictive rule under which you can't recover anything if your own carelessness was 50% or more responsible for the accident. And a handful of tight-fisted states don't allow you to recover any compensation at all if your fault is any more than "slight" compared to the others involved -- or, worse, if your own carelessness contributed in any way to the accident. (This is called "contributory negligence.") You can find the rules for your state in How to Win Your Personal Injury Claim, by Joseph Matthews (Nolo).