Question: My mother's car died on her when she turned out on the highway from a secondary road. Before she even had a chance to do anything, she was hit in the rear by a truck that turned onto the highway behind her. I believe her car is totaled. No one was cited. Who is at fault? Answer: My opinion is that the person that rear-ended your mother's vehicle would be the at-fault driver. But my opinion doesn't matter. If there is a disagreement among the drivers about who is at fault and both place auto insurance claims against the other's car insurance policies, then the insurers of the vehicles involved will be the ones to sift through the details of this accident and ultimately assign fault. It's unfortunate timing that your mother's vehicle died just as she was getting on the highway, a time that one usually starts to accelerate. But sometimes cars die, slow down, or come to a complete stop due to mechanical issues, road debris or traffic -- and drivers are supposed to be ready to take action and stop if necessary. This is why in my opinion the other driver is at fault for rear-ending your mother. The good news is sudden, unexpected events -- such as hitting the car in front of you - are the very definition of an accident and the reason drivers have car insurance in the first place. Not noticing a car slowing is negligent; thus, the other driver's insurance company should see that its driver is responsible for the damage to your mother's car and accept a claim under its driver's property damage liability coverage. If the other driver believes your mother was at fault, then he may make a claim against her property damage liability coverage for his truck's damage. If this does happen, then as I mentioned the insurers would look into the accident and make its own determinations of fault.