As reported by American Association for Justice (AAJ):
In a ruling with wide implications for federal preemption and vicarious liability, the U.S. District Court for the Southern District of Florida on September 14 declared the Graves Amendment unconstitutional. That amendment had given immunity to automobile rental agencies for harm caused by their vehicles (Vanguard Car Rental v. Huchon, Case No. 06-10082-CIV-Moore/Garber, USDC SD FL).
For more information on this subject matter, please refer to the section on Car and Motorcycle Accidents.