Conflicting instructions at a school junction
On a Tuesday morning you approach a junction beside a basic school holding an outdoor assembly. On the corner stands a permanent NO RIGHT TURN sign. Twenty metres before the junction a yellow-and-black temporary sign on a trestle directs all traffic to turn right, because a burst water main has closed the road ahead. Your traffic light is green. In the middle of the junction a police officer faces you, right arm raised with the palm towards you, whistle blowing. Behind you a taxi is hooting. A pedestrian on the pavement is gesturing and shouting that the road ahead is flooded. Your windscreen is dusty from the harmattan and the wipers have smeared it.
1. What does the officer's raised palm mean for you, and which of the four instructions - the permanent sign, the temporary sign, the green light, the officer - do you obey?
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Raised palm, arm up, facing you: stop. It is directed at your approach.
Hierarchy of instructions, strongest first:
- The police officer - a person controlling the junction in real time. Their signal overrides the lights and every sign.
- The temporary roadworks sign - it describes today's actual conditions, so it overrides a permanent sign that describes the road as it normally is.
- The green light - permission to proceed, but only in the direction that is actually open.
- The permanent NO RIGHT TURN - suspended by the closure it cannot know about.
The reasoning is not 'police rank highest' as a fact to recite; it is that the most recent, most local and most human instruction is closest to the actual hazard. So: stop for the officer, and expect to be waved into the right turn that the permanent sign forbids.
2. The officer now waves you to turn right while the light is still red and the permanent sign prohibits it. What do you do, and what do you check before moving?
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You obey the officer. The prohibition exists to protect a hazard; the officer is managing that hazard directly.
But the officer's wave is permission to make a manoeuvre, not a guarantee that the manoeuvre is clear:
- Signal early so the hooting taxi and anyone behind understands you are turning.
- Mirrors and blind spot - a motorcycle may already be filtering up your left as the traffic slows.
- The crossing itself - pedestrians leaving the school assembly may be walking through the mouth of the junction on the officer's blind side.
- The road you are joining - give way to anything already on it; a green light or an officer's wave never gives you the right to drive into another vehicle.
- Move slowly and be ready to stop if the officer's arm drops or a colleague steps out.
Do not treat the red light as something you are 'breaking' - you are following the direction of the person controlling the junction - but do not treat it as licence to proceed at normal speed either.
3. Suppose you arrive later the same day, the officer has gone, and the light is green. How do you decide what to do about the permanent sign and the closure?
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Keep the same logic without the officer:
- Confirm the closure is real. Look for barriers, cones, a works vehicle, water on the road. A sign on its own can be left behind after a job is finished, or moved by wind and traffic.
- Treat the temporary arrangement as current reality - it exists because the normal route is impassable, so following the permanent sign would send you into a flooded trench.
- The green light only covers the junction, not the turn. Before turning right you still give way to oncoming traffic, to pedestrians already on the crossing, and to the road you are entering.
- If the temporary signing is knocked over or unclear, do not guess a route through a works site. Stop where it is safe, and take the clearly open exit.
The green light tells you the junction is open to you; it does not overrule a closure that the light knows nothing about.