They have, but in the heat of the moment even the best of us can occasionally fail.
They had a guardian angel that night.
Speaking as someone who’s been in a similar situation - chances are the truck was just loud and wasn’t actually going that fast - because a large truck doing 50mph doesn’t stop quickly at all. The incident as recounted does not really make sense.
I was riding a motorcycle through a residential area on a street posted for 35mph. A child ran out in front of me; since I had seen the family well in advance I was actually doing 20mph and was easily able to stop in time. I was then beset by the family and neighbors who were all screeching about how I was going “twice the limit” and “SPEEDING SPEEDING SPEEDING” and should be ashamed of myself. I hadn’t been speeding, they simply had judged my speed by the noise my motorcycle was making (which is how most people ‘estimate’ a vehicle’s speed). My pleas fell on deaf ears, the police showed up and it kept getting worse and worse.
Unfortunately for the idiots in the lynch mob, I had a helmet camera. Even more unfortunately, I had captured the entire thing including a view of my speedometer which clearly indicated my reduced speed. I showed it to the cops and they eventually let me go.
I later found out that the police often disregard citizen estimates of speed due to just how bad people are at estimating speed.
There’s a school zone here that some old biddies sit around in lawn chairs and shout at people that go through ‘too fast.’ The zone is posted for 20mph. I roll through in first at 10-15mph. They routinely shout at me for ‘going too fast’ even though the cops have shown them with radar that I’m simply not speeding.
They should have had a kid leash.