Sure you can.
The owner of the car that was wrongly parked still has the ability to sue. They should get the other driver's information and file a claim on their lawsuit.
Well if the cars' motor stops then yes it could be considered broken down
Your horseless carriage is parked outside this very door, sir. My typewriter has a broken carriage.
Your steering linkages are faulty, or there is an obstruction to your front wheels, or the road markings forbid a right turn, or you are parked very close to a wall on your right side.
back brake springs weak or broken! or a brake part is broken.
The insurance company has no reason to raise your premium, the situation was completely out of your hands.
Broken "Parking Pawl"?
As long as the parked vehicle is parked properly and not illegally parked in any manner, then the vehicle that rear-ended the parked car is at fault. Now if the parked car is sitting illegally (such as double parked or parked in a no parking zone, etc.) then the parked car is at fault or even both the parked car AND the car that hits it are BOTH at fault.
As long as the evidence (broken glass, skid marks, etc.) support your son's version, he'll have no problem.
When Communist North Vietnamese T54 tanks parked on the South's Capital front lawn on 30 April 1975.
The person's who parked it there, (its parked illegally.)Not your fault.
Parked was created in 2011.