It depends. I know that sounds like a lawyer answer, but determining liability for a car accident in Arizona is not as simple as looking to see if the police gave a citation. First, under Arizona law, the fact that the police gave a civil traffic citation or a civil traffic conviction was entered is not admissible in a civil action to prove negligence A.R.S. § 28-1599. Second, Arizona uses the concept of comparative fault, so two or more parties may bear some percentage of the responsibility for a crash, regardless of who got the citation. And finally, the police may just be mistaken because they misapplied the law, relied upon evidence that would not be admissible in court, or just came to the wrong conclusion. When looking at liability for a car accident case, I am more concerned with the evidence that the police gathered at the scene and not necessarily the opinions or conclusions that they drew in issuing a citation. If you have been involved in a car accident and you don't think you were entirely at fault, it is always best if you consult personally with an attorney who is experienced in car accident cases and traffic law.