No you would not be responsible. The car that hit you in the rear, pushing you into the car in front of you would be responsible. You were no negligent, if you were at a complete stop when you were rear ended. This answer would not be found in your insurance policy. This does not mean that you will not be sued, as the first car occupants may want to sue both cars. Your insurance company adjuster should be able to let you know your liability situation as well. If you are sued, be sure and turn this over to your own insurance company
I've spent hours in depositions and at trials where precisely the issue that you raise has been litigated and the answer is not a clear and simple "NO". The negligence determination itself is not in your insurance policy, the determination will be made first by the insurance adjusters using various insurance fault standards, as well as the rules of the road set down in statutes and regulations.
You had a duty to stop a reasonable distance behind the car in front of you. Your liability will depend on how far behind the car in front you were stopped, whether weather and road conditions would have made it reasonable to come to a stop further behind that vehicle, whether you had your foot on the brake, the condition of the tread on your vehicle, and other factors.
On one end of the spectrum we have you stopped well behind the car in front so you can see the point at which that car's rear tires met the road, it was a sunny dry day, you had your foot on the brake, and your tires were in good condition. You win. On the other end of the spectrum, it is raining and the road is wet, you stopped 3" behind the bumper of the car in front, you had old bald tires and you did not have your foot on the brake. You have problems. It is up to the adjusters, and possibly attorneys and a court to determine fault.
This is why the rules of the road require that one stop a vehicle a safe distance behind another vehicle in traffic.
Make sure you've reported this to your insurance company, let them fight this battle for you.
This answer is provided for informational purposes only. Actual legal advice can only be provided in an office consultation by an attorney licensed in your jurisdiction, with experience in the area of law in which your concern lies.
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