It depends on how the insurance companies of each driver sees it. You both could be charged with "undue care and attention", or the person backing out did so in a hurry and hit you, it would be their fault. If they hit you on the side any part of your car such as a back fender (meaning you were well out of your stall and they just backed into you) it's their fault.
Marcy
In many state jurisdictions, such as Georgia, police are required on the scene. Although, many time an incident such as this occurs on private property and a police officer is unable to issue a citation. However, they can issue a police report of the incident. many times this is used by insurance companies to establish fault. If fault cannot be established then each insurer would default to their own coverage.
Mark Link, PC
Depends on the jurisdiction, but typically, two vehicles backing up is a 50/50.
both of you for not looking back
The person who is backing out of the parking space
the car backing out.
Parking sensors are for the driver to be able to tell a proximity of other vehicles and objects around the car. This is a helpful tool if backing out of tight spaces and places that have a lot of things scattered around the vehicle.
A vehicle traveling in a parking lot has established use of the lane and the right of way. A vehicle in a parking space and backing into the lane must yield to oncoming traffic. Therefore, if a vehicle is backing out of a parking space and pulls into the path of an oncoming vehicle that has already established the lane, the vehicle backing would be at fault for the accident. However, if the vehicle which established use of the lane had an opportunity to avoid hitting the vehicle backing out of the space and failed to do so, there could be comparative negligence on both vehicles or on the one who had the opportunity to avoid the accident.
Both of you are probably at fault. If you see another person backing you should stop and signal the other driver if possible. Otherwise stop and wait until that driver completes his backing maneuver.Added: It is the obligation of the backing driver to ascertain that his movement does not interfere with any other vehicles. In this instance, you both apparently failed to do so.
You are. Improper backing.
Backing up--it is your fault.
The person backing out. If you were in the lane/road behind them they needed to use caution when backing out.
You need to practice backing up slowly in a deserted place with a curb that is out of the way of other moving vehicles, perhaps the outer limits of a mall parking lot. Repeated practice will give you a sense of when your car is near the curb.
Any time the driver who is backing is at fault, in all 50 states.