The Pittsburgh left is a colloquial term for the practice of oncoming traffic yielding to a driver at an intersection who is turning left even though the driver turning left is the one required to yield. Before opposing vehicles going straight advance; the straight-driving vehicles may signal their yield by flashing their headlights or with a wave. This behavior is associated with the Pittsburgh, Pennsylvania, area and came into vogue because of its hilly terrain combined with the preponderance of two-lane roads. It is an illegal and controversial practice.
The maneuver has been referred to as a Boston left or New York left, but those maneuvers may refer to when the left-turning driver rushes to turn left before the straight-driving driver can advance, regardless of whether the straight-driving driver yields or not.
Legality The Pittsburgh left has no basis in law. Failing to yield to oncoming traffic while navigating a turn is a traffic violation, and is prohibited in the Commonwealth of Pennsylvania. In Ontario, Canada, such a turn is considered stunt driving under the provincial Highway Traffic Act. O Reg 455/07, s 3(8)(iv). https://www.ontario.ca/laws/regulation/070455
See also Pittsburgh parking chair Michigan left
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