Night driving, a dark-clothed pedestrian and high beam
You are driving at night on a Bulgarian road outside a town. The limit is 90 km/h and you are doing 80 km/h. The road is unlit and straight. You are using high beam because there is no oncoming traffic. A pedestrian in dark clothing appears at the right edge of the road about 60 metres ahead, walking along the carriageway. Your reaction time is about 1 second. At 80 km/h, your dry-road stopping distance is roughly 60 metres; on high beam you can see about 100 metres, but the pedestrian is hard to see against the dark background. A car with high beam approaches from the opposite direction about 150 metres away.
1. Using the numbers, assess whether you can stop for the pedestrian and what you should do.
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At 80 km/h you cover about 22 metres per second, so reaction takes about 22 metres. Add the dry braking distance, and the total stopping distance is roughly 60 metres. The pedestrian is about 60 metres ahead, so stopping exactly in time is the best case with no margin, and the pedestrian is hard to see. That is too close for comfort.
You should dip your headlights for the oncoming car, but only after you have identified the pedestrian, and you should brake firmly and early rather than waiting. Reduce speed immediately, move slightly left if it is safe to give the pedestrian room, and be ready to stop. Do not swerve sharply at night, because you cannot see the verge. Sounding the horn may help warn the pedestrian.
2. How does the oncoming car with high beam change your plan?
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The oncoming car's high beam can dazzle you and reduce what you can see. You must dip your own high beam so you do not dazzle the other driver, and you should not look directly at their lights; look toward the right edge of your lane to keep your position. Dipping your lights will shorten how far you can see, so you should already have reduced speed before the car gets close.
The pedestrian is the priority. Keep braking and be ready to stop, but do not accelerate to pass before the oncoming car arrives. If the dazzle is severe, slow further and, if necessary, stop safely rather than continue at 80 km/h with reduced vision.
3. What should you do after passing the pedestrian, and what does the law expect about high beam?
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After passing, return to high beam only when it will not dazzle anyone, and keep your speed down until you are sure the road is clear. Check the mirror and keep watching the verge, because where there is one pedestrian there may be others.
The law expects you to use high beam on unlit roads when it does not dazzle other road users, and to dip it for oncoming traffic and when following another vehicle. Using high beam into oncoming traffic is both dangerous and contrary to the rules. The point of the case is that seeing far is not the same as stopping in time: speed must match the distance you can actually see and stop within.