At 9:30 Thursday morning, October 7, 2010, Gordon Parks and his guide dog Wendy were walking from their home to downtown Moorestown in the New Jersey suburbs just outside of Philadelphia.
They had to cross Camden Avenue, a two-lane street with fast traffic.
Less than a 5-minute walk away, they could have crossed at a traffic signal with Accessible Pedestrian Signals that had been installed at Gorden's request several years earlier.
However Gordon thought that crossing at the signal was too risky because of the turning cars, so they usually crossed where there was no stop sign or traffic signal (see photo to the left).
This morning, Gordon was wearing an orange vest to make the crossing safer.
Just as they entered the second lane, they were hit by a Dodge Ram pickup truck coming from their right.
Gordon was thrown back and died the next day, his dog Wendy was killed immediately.
The driver said he never saw them-- they may have been hidden by the truck's windshield frame.
Three weeks after the tragedy, I went to the intersection to analyze the situation.
Situation of Confidence sometimes; Situation of Uncertainty sometimes
I evaluated the situation at that crossing using hearing, which is what Gordon used.
The first time I analyzed it (about 3:00 Friday afternoon), it was clearly a Situation of Uncertainty.
The second time I analyzed it (Saturday evening at about 8:00), it was clearly a Situation of Confidence.
(You can click here if you want more details of the analysis.)
I made the video to the right on Friday afternoon while I stood where Gordon and Wendy had started their crossing (the link may not be accessible from restricted sites).
When the video begins, it is quiet and no vehicles can be seen in either direction, and yet it is not possible to hear a pickup truck approaching from the right until it is about 4 seconds away.
For someone like Gordon who relies on hearing to cross, this would be considered a Situation of Uncertainty because even when it seems quiet, it isn't possible for anyone to hear the vehicles well enough to be sure whether or not it is clear to cross.
However at 8:00 the next evening at the very same crossing, whenever it was quiet, I could hear all the traffic from several blocks (at least 13 seconds away).