Offcourse automatic cause more accidents than manual. When driving manual car, the visibility and mental state to drive the car is always active becasue we are using both are hands and legs in order to operate the car. While driving automatic car, there is no use of hand and thus we loose our visibility as well from the road as we don't have to think much on when to change the gear. On the other hand driving manual car is a tough job specially when driving in the traffic. It requires full concentration and thus we have are more active on the road which ultimately results in less accidents on the road.