A failure to match up reports by itself does not mean anything--in fact, it's fairly common for the two parties in a two-car accident to have different views of what happened.If you are found to be at fault in the accident and the other driver (or his/her insurer) sues you and wins (which they would likely do, if you were at fault), you would have to pay for the cost to repair his/her car (or its current blue book/fair market value if it has to be totaled), his or her other out-of-pocket costs (like towing; renting a car; etc.); his or her medical costs, if any; pain and suffering if he or she suffered a sigificant injury; and his/her lost wages, if any.