Dead traffic lights and a gendarme's wave in a Douala downpour
It is 19:40 in a Douala suburb at the height of the long rains. You are on a two-lane urban road approaching a four-way junction. The traffic lights have been dead since 17:00 after a transformer fault. On your approach a 'Cédez le passage' sign is half hidden behind an overgrown bougainvillea, and the white give-way line on the tarmac is worn down to a few grey patches. A gendarme in a reflective vest stands in the middle of the junction. He turns, looks at your lane, and waves you straight through with a broad sweep of his arm. At that same moment your headlights pick out a woman carrying a child, still walking across the worn zebra crossing about eight metres ahead of your bumper; she is looking down at the water she is stepping through. An oncoming vehicle with only its left headlamp working is about 60 metres away, and a large puddle covers your side of the lane.
1. Rank, in order, the instructions and signals that govern your movement through this junction, and state what you actually do in the next five seconds.
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The order of authority in the traffic rules is: (1) instructions from a police officer or gendarme directing traffic, (2) traffic lights, (3) road signs, (4) road markings, (5) the general default rules. So the officer's arm signal outranks the dead lights, the give-way sign and the worn line. He has authorised your lane to move.
That authorisation is not a guarantee that the way is clear. No signal from anyone relieves a driver of the duty to avoid hitting a pedestrian already on a crossing. So: ease off, cover the brake, creep forward at walking pace and stop short of the zebra. Let the woman and child finish crossing, then proceed straight through. Do not sound the horn at her and do not squeeze past behind her - you cannot see her footing on a flooded crossing. Keep watching the officer for a change of direction; if he waves again impatiently, raise a hand to acknowledge and point at the pedestrian so that he can see why you are stopped. His authority settles who goes first; it does not transfer the pedestrian's safety to him.
2. Does the overgrown sign and the worn-out give-way line reduce your obligation at this junction? What would the position be if the sign were completely missing?
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No. A sign's legal effect comes from it being placed at the junction, not from your ability to see it. The overgrown branch and the faded paint change nothing about the obligation: you must approach a junction whose priority you cannot read at a speed and in a gear that let you stop within the distance you can see to be clear. In rain at night, on a flooded surface, that is far below the urban limit - think 30 km/h, not 50 km/h. The worn line only means you cannot use it as a braking reference; pick a fixed point before the junction instead, such as the corner of the building on the right.
If the sign were genuinely absent and there were no markings, the junction would be unmarked and the default rule would apply: give way to vehicles approaching from your right, and do not enter unless you can clear the junction without blocking it. The dangerous assumption is 'nothing is marked, so I have priority'. That is exactly how side-impact collisions happen at junctions where a driver reads an absence of paint as an absence of rule.
3. The oncoming vehicle has only one working headlamp. What do you assume about it, and how does that change your speed and your line?
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Never assume a single headlamp means a motorcycle. It may be a car with a failed lamp, in which case it is much wider than the light suggests; it may be a three-wheeler, or a stationary vehicle showing one sidelight. Assume the widest plausible object and the slowest plausible speed.
Line: stay on your side of the centre, but do not hug the flooded kerb either - the puddle hides potholes, open drains and pedestrians stepping around the water. Reduce speed to 30 km/h or less. Dip your headlights so you do not add glare to a driver who already has reduced vision, and watch the spray plume at the moment he passes, because a pedestrian may step out from behind it. Do not flash your main beam to 'claim' the road: it produces glare and conveys no information. Keep an escape in mind - if he drifts over the centre line, your options are the left edge of your own lane and stopping, not the flooded verge where you cannot see what the water is covering.