Was it? I don't know as I wasn't there. You may want to rephrase this to make clear what you are asking.
The car in motion is ALWAYS at fault when it hits a stationary vehicle.
In the UK it can, if the driveway is private property.
Yes. Being illegally parked does not affect fault. If you strike a parked vehicle, it is ALWAYS your fault because you have a duty to ensure the way was clear before moving.
The person who is backing out of the driveway is completely at fault. Even if the other party was illegally parked, the driver of the other vehicle has the responsibility to look behind them for clearance.
Let your insurance company handle it. They do it all the time.
The person who is backing out
The driver of the backing vehicle. The fact that the car was parked illegally is irrelevant. The onus is always on the driver of a moving vehicle to ensure the way is clear before backing up.
If one vehicle is sitting parked and one is in motion, then logic dictates the vehicle that was in motion is at fault and therefore responsible for the damages.
I parked my car in the driveway
In New Jersey, parking in a driveway is typically allowed as long as the vehicle is not blocking the sidewalk or encroaching on the public right-of-way. However, it's always best to check with your local municipality for any specific regulations or restrictions that may apply in your area.
Not if you own the driveway. Your property, your land. IN UK you must tell DVLA that the vehicle is off the road by submitting a SORN
It is the person who is blocking the private driveway's fault because they should have known not to park in front of a private driveway in the first place. However, if the private driveway is not marked with a sign of some sort to let people know that it is private, it may be the driveway owner's fault.