Some states have a presumption that trailing vehicle is at fault in rear end collisions, others do not. Generally, police will initially indicate the trailing vehicle is at fault because every person is expected to keep a safe stopping distance between them and other vehicles, but if there is a lawsuit, or a criminal action, that can be challenged in a number of ways: Did the person who stopped create a hazard on the roadway; you were driving in a reasonably prudent manner but other factors lead to the collision; Importantly, some states have comparative fault rules, which means that if there was a lawsuit, the jury would determine how much each person was at fault for the collision. Thankfully the police don't make that determination. Glad to hear no one was hurt.

Did you receive a citation? What is the alleged violation? You can always look up the code to get a better understanding of what conduct is deemed unlawful. You may want to contact a local criminal defense attorney. Many offer free initial consultations, and depending on the circumstances, may be able to assist you. Good luck! Stefano L. Molea, Esq.* Molea Law: Criminal Defense 760.383.1766 http://www.molealaw.com *This answer is provided for educational purposes only and is not intended as the practice of law in any jurisdiction in which I am not licensed. The answer does not constitute legal advice nor does it create an attorney-client relationship. The answer is based only on the information provided, and may be inaccurate in the context of additional facts that have not been provided. The questioner should be aware that I am only licensed to practice law in the state and federal courts of California. Accordingly, before taking any action or refraining from taking any action, the questioner should consult with an attorney licensed to practice in his or her jurisdiction.