Crashes often occur at intersections because these are the locations where two or more roads cross each other. Activities such as turning left, crossing over, and turning right have the potential for conflicts resulting in crashes. Specifically, the US National Highway Traffic Safety Association (NHTSA) found that turning left is a leading critical pre-crash event and occurs in 22.2 percent of all crashes. Further, approximately 61 percent of crashes that take place while turning or rossing an intersection involve a left-hand turn.1