I was driving approximately 30 miles an hour with my foot on the accelerator when the automatic braking stoped the car dead. The automatic brake message flashed on the dashboard at that time. There were no cars or anything in front of me on the road. I was then rear ended by the car behind me. The car was taken to a collision shop, and there was a scan done on the car. There have been no other inspections of the cars braking system as far as I know. The problem was reported to my insurance company, Geico. The problem was reported to the police officer responding to the scene of the accident and the collision/towing company.