When drivers or pedestrians are stopped before crossing a roadway (or turning left or right) they need to be able to see to the left and to the right far enough to safely make their crossing (or turning maneuver) without interference from oncoming traffic.
Federal, state, and sometimes local standards are in place for engineers to use for design, construction, and maintenance activities to ensure that minimum sight lines, sight distance, and sight triangles are provided at intersections and pedestrian crossings.
The required sight distance to the left and right of the stopped driver or pedestrian is related to the speed of the cars approaching on the main street. The higher the main street speed is the longer the required sight distance will be. And, as the pedestrian or driver has to travel farther to cross the main street so will the required sight distance to the left and right be longer.
Sight distance, sight triangle, and sight line accidents require a careful review of the available sight distance, and then a comparison to the required sight distance. And, in many cases, the traffic control devices in use to warn drivers of possible sight distance issues may be in question.
It is not uncommon for "remodel"-type projects where a pedestrian, bicycle, or multi-use path is added through an already-developed area, and the needed sight distance is not provided where the new trail crosses a road. We sometimes also see this when new intersections are added to older roadways, and the available sight distance may not meet the required sight distance. And, when roadways are widened, and the crossing or turning distances for drivers and pedestrians is now increased with the wider main road, the existing sight distance may not meed the requirements if efforts are not made to improve the old sight distance.
Mr. Marceau has reviewed and testified in many crash cases involving driver and pedestrian sight distance issues. He is experienced in explaining the technical aspects of sight distance to juries and to attorneys.