fisherman wrote:
Tests carried out by the officer showed that, had the driver obeyed the recommended 5 mph limit he would have stopped well short of the child.
Oh, I do so love that argument
It's one of the mainstay arguments of the 'speed kills' brigade, and has taken most people in - including police accident investigators, evidently.
It's one of those arguments which appears to make perfect sense - until you think hard about it, and then realise that the logic behind it is fundamentally and fatally flawed.
Had he obeyed the 5mph limit the collision would certainly not have occurred - but
not because of the shorter stopping distance at the lower speed.
The collision would not have occurred for the simple reason that he would not yet have been anywhere near the spot where the child ran out
at the time at which he ran out. He would not even have needed to brake at all.
Conversely, had he been going faster (25-30mph) then he would have been well past the spot where the child ran out
at the time at which
he ran out, so nothing would have happened.
Alternatively, had he been travelling at 5mph, but had entered the parking lot earlier in time than he had, he might then have been much closer to the spot at the time the child ran out, so might still have hit him, perhaps even at 5mph if it was too close for him to get his foot onto the brake.
And that may very well have been higher than the impact speed that actually occurred.
As an aside, how is any driver supposed to know when they're doing 5mph when most speedos don't even register until 10mph or above?
The fatal flaw in the argument is that they take the starting point as that when the driver first realises the need to take action. And then they just hypotheticate a different speed based on the same starting point, and come up with a completely nonsensical conclusion.
The laws of physics dictate that you cannot change the speed of an object without also changing its position at a given time - but that's precisely what that argument attempts to do.
That driver was, quite simply, in the wrong place at the wrong time, although it may be that he could have been more aware of the potential hazard than he was.
Perhaps he was watching his speedo.
Cheers
Peter