Legal Question in Civil Litigation in Tennessee

You rights and responsibilities as to the rental company are governed by your rental agreement. Most of those agreements provide that the Renter (that's you) are responsible for damages to the vehicle. That's why they always try to sell you insurance. So most likely you are responsible. You should contact your personal insurance company and see if your policy on your car would cover you.

You may have a claim against your friend (yes, I know that's distasteful) if he/she was negligent in the operation of the car. Alternatively, you might also have a claim against the other driver. Of course both of these depend on the facts of the accident.

Hope this helps.