If the Pennsylvania Supreme Court decides a municipal agency cannot be held liable for damages caused by the involuntary movement of a government vehicle, then the motor vehicle exception to governmental immunity under the Tort Claims Act is dead, an attorney told a full complement of the high court Wednesday.

Attorney Michael Shaffer of Shaffer & Gaier made the argument in the case Balentine v. Chester Water Authority on behalf of the estate of a man killed in a two-vehicle accident involving a Chester Water Authority truck. The Water Authority truck had been parked on the street with its motor and strobe light running, but the driver had not been inside the vehicle when it was hit by the second vehicle, which caused the truck to pin the decedent.