I say "not necessarily". As long as the major factor of human beings are involved, any decrease claimed are merely claimed and not facts. Safety is always a case-by-case thing. It may decrease accidents in parts of the world such as Sweden (where it is required by law to have DRLs), but it is more of a distraction in California than it is a piece of safety equipment.
Opponents of mandatory DRLs have studies that show DRLs have no more affect on decreasing accidents as driver education. People don't see what they don't look at. Period.
