If you reverse your car and then collide with a parked car , the person who did the reversing is At Fault.
As long as the evidence (broken glass, skid marks, etc.) support your son's version, he'll have no problem.
As a general principle, the person operating a moving piece of machinery is responsible for damage to any non-moving obstructions. Whether or not the other car was legally parked is irrelevant. It could be abandoned in the middle of the road and it would still be the drivers responsibility to see and avoid it.
It is not an offence to back out of a driveway, but it is an offence to back across a lane of traffic.
The person's who parked it there, (its parked illegally.)Not your fault.
Only onto a major road or junction, or by a local ordinance. Otherwise we would all have a U shaped driveway. You need a turn-around area in your driveway. It certainly is not safe to come to a stop on the highway and back into your driveway nor is it safe to back out of your driveway onto the highway. I have a straight driveway and it's not illegal to back out onto a minor residential street.
Just like any other accident,, You are responsible for the damage you caused. Either file a report with your insurer so they can cover the damage you caused, or pay them yourself for the Damage. It's your choice. The law requires you be Financially Responsible.
The person backing out of the driveway.
Yes
if you're reversing into your driveway and someone hits you its their fault. you were moving away and they wern't paying attention. Now if you went back into the street to straighten out and back back in then it might be your fault, but if you were reversing the whole way and never came back out of your driveway it would be theirs
yes
Building his mothers driveway
You know the answer: you hit a parked car! You're absolutely liable. On one hand, you should have been looking while backing out so it would be your fault. He may get a citation for parking there, but you could have avoided an accident by looking first. You will be lucky if you are not cited for reckless and dangerous driving. (In some states, contributory negligence on the part of the parked car's owner could reduce your liability, but you would still be at fault. Your best option is to report vehicles that are illegally parked and avoid any possible accidents.)