Your insurance company should have whats called an extrapolation artist that can determing with all the facts fault. Police officers are not trained to determine fault, especially if they were not there.
Police don't always determine the fault especially the private property incidents. What the police report usually does is tell the facts of what happened and what any witnesses say they saw as well so in situations where no tickets are issued or cause of fault is listed the insurance companies will get together and determine the fault. Sometimes when two cars back into each other there may just be levels of fault whereby each party may be partly at fault which never benefits anybody.
Whoever the police report charges with the accident.
If you are both moving, the one at fault is whoever the police officer says is at fault on the accident report. That's all I can tell you with this information. I hope you called the police. They will say you backed into them and you will say they ran into you. Without a police report faulting one of you, the insurance company will say both are 50% at fault which means each pays for their own damage.
An insurance company can assign fault regardless if a police report is filed or not. A police report is simply a report made by a neutral party at an accident scene. I believe there have been cases where insurance companies have assigned fault to one party when the opposing party was initially named at fault in a report.
Insurance companies determine fault by looking at police reports, taking statements from the parties involved and witnesses, and looking at the vehicles.
The default answer is the car that is moving is at fault unless the moving car has the right of way. However parking lots are messy and there will be no police reports unless the damage is over a certain amount ($2500 I think). The best thing to do is handle it without insurance companies.
The car drectly behind you who hit you. The police report will assign fault. If you are not at fault, the person who is will be responsible for the damage. Get a copy of the police report from the investigating agency and give it to your insurance agent. Thay should take it from there.
Since parking lots are not considered public roadways - normal traffic regulations do not apply there and it is doubtful that you will find a police agency who will conduct a collision investigation to determine 'fault.' It will be up to your insurance companies to decide which party the the fault lies with.
If you strike him - you are at fault. He can be charged with the No Parking violation but YOU are charged with the collision.
Usually their is no fault associated with parking lots. I'm sure your insurance company looks at it as your fault.
Is it possible that you are both at fault? The person backing out is at fault. He was stopped and should have been looking before backing out. However, if the parking lot is designed so that you can only go one way, then you may be at fault. The insurance companies will look at the police report and fight it out.
You are at fault.