page 67: Another point of concern is the fact that approximately 85% of drivers are committing violations between 0.3 and one second based on the available data in the before period. Based on observations and studies conducted at ITRE by Milazzo et al., the majority of RLR related collisions do not likely occur until a couple of seconds into the red indication, provided that leftturning vehicles in the opposite direction do not have a permitted indication and are trying to “sneak” through the intersection during the all red portion of the cycle (2). If collisions are taking place two or more seconds after the onset of red (in the situation where permitted lefts are not allowed), then one may ask why agencies are providing such short grace periods or, one may also wonder why agencies do not extend yellow times to allow drivers a longer period to clear the intersection before the onset of red.

Most vendors selling automated enforcement systems allow a grace period of 0.3 seconds. This grace period on a standard 45 mph street (assuming a conservative estimation of the actual speed) allows a distance of approximately twenty feet past the stop bar. Twenty feet is approximately the length of a full size pick-up truck. This is a trivial distance/time to many drivers, which is one of the primary arguments against most current camera systems.