No, you are not. Unless there is an injury or death, you just exchange information and pay the other party or let insurance figure it out. "You must call the police or the CHP if the accident caused a death or injury." http://www.calbar.ca.gov/Public/Pamphlets/AutoAccident.aspx#... In WA, you also have to report if there was over $1k in damage. But it is obviously easy to estimate it is under that while at the scene of the accident. http://apps.leg.wa.gov/rcw/default.aspx?cite=46.52.030 Most states are the same. If there wasn't an injury and it isn't impeding traffic, the police don't care.