Wow that is unfortunate, thanks for the clarification, I'm not familiar with the area or Segways, though I do go to DC every few years for the museums.
The first accident was coming down 15th by the treasury where there are large bollards on the sidewalk- an older gentleman in his sixties was zipping around and he went full speed down the sidewalk and clipped the wheel on the very edge of one and it spun around throwing him off- very much like going over the handlebars on a bike. I assume he broke something between his wrist and collar bone (or both).
The next one was going off a sidewalk if memory serves but was minor.
The third one was over on the north side of the Capitol- we were idling around while the guide was talking and this older lady in her fifties or sixties was kinda floating through the crowd but didn't seem out of control- she went around this big tree and either lost control or wasn't paying attention as it was getting dark and went full speed around the side of a tree and ran right in to a lamp post. It knocked her out.
I was getting nervous riding back feeling like we were all going to experience some mishap.
Kinda feels like age of the people may have been a factor here. Segways do require good reaction times and constant awareness of your surroundings because they don't stop (even when stationary they have power to the wheels keeping them balanced, and if you move they move) and it the tour guide thought anyone was too young, old, or otherwise not capable to control the vehicle, they shouldn't have let them go out in public.
Not saying that was the only factor, it could easily have been the tour guide not giving adequate safety instructions or simply people ignoring those instructions... or a mixture of all three!
