Thanks every one. Both of the cars were about 70 MPH on the highway (based on the report) and it was 12:30am last night. The original words that the policeman said about the other driver is "He lied to me, he said he didn't hit any car", That's why the police gave him instead of me a citation. Neither of the driver was DUI. I think the fact is he tried to change lane but didn't look carefully enough and my car was in his "dead view" (or dark view?) and once he changed, my car already run in the same position, my car's scarch is on the right side (based on the head is 1, right side is 2, 3, 4, 5, 6,7), the position is 4, 5,6.