A statute of limitations is a law that only allows claims to be brought for a certain period of time after an event or action. When relating to personal injury, it means that there's a specific period of time where you can bring a lawsuit against a person or company you think is at fault.
Statutes of limitations exist to make sure that the evidence in a case is "fresh" — that is, that evidence and witness testimony are likely to still be useful to the court in figuring out what happened.
This means that you only have a certain amount of time after an accident to start your claim. How much time depends on which state you live in. Always make sure to speak to a lawyer to confirm, but here's a general list of the statute of limitations by state:
Don't automatically assume that nothing can be done if the statute of limitations has passed. There may still be a way to resolve your case in a satisfactory way. You'll need to talk directly to a lawyer to discuss your options.