In practice, a court would consider what can be reasonably expected of a competent motorist
You have gone so far as to incriminate the motorist without trial, in your opinion he is guilty without doubt,
No I haven't. See my quote from above.
There is a particularly famous legal case, Fitzgerald V Lane & Patel 1988, whereby it was declared that a pedestrian was as equally at fault as a pair of speeding motorists for he crossed the road without paying attention. The claimant was deemed to have contributed negligently to the act and was therfore awarded a fraction of the damages he would have otherwise been awarded.
I think you are referring to the case where two motorists both hit a pedestrian on a pelican crossing that was on red (for pedestrians), and the court did indeed decide that the pedestrian was equally to blame as the motorists were.
However, I was responding to your comment "Roads are dangerous because ...", which is a different matter. There is no doubt that motor vehicles bring almost all of the danger to the situation. In their absence, there would be no need for other road users to be so alert to danger.
My point is that, far from acting as though they own the road, motorists should take the lion's share of responsibility for ensuring that the presence of their motor vehicle poses as little danger as possible to other, vulnerable road users, and should accept the fact that it is they who are a guest in the public space, to be tolerated by other road users provided they abide by some very stringent rules.
Incidentally, I apply this principle to myself as well, as a motorist with over 350,000 miles of experience, who pays fuel duty, GVED (£30.00), insurance, and tax on that insurance, but who has never, ever paid road tax, having been born decades after the latter was abolished.
