Flashing amber, a police officer and a half-hidden diversion sign
At 18:45 on a wet evening you are driving south on the M1 towards Port Louis in heavy rain. The traffic lights at a busy junction are out and are showing flashing amber. A police officer in a reflective jacket is standing in the middle of the junction. As you approach in the left lane, intending to turn left into a side road, the officer turns towards you and raises a hand, palm out. Beyond the stop line is a yellow box junction; the exit on the left is partly blocked by a bus that has stopped at a shelter. A temporary yellow diversion sign on the left is half covered by a fallen branch, and the left-turn lane marking is worn. Your wipers are on fast and visibility is about 40 m. A pedestrian with a hooded coat waits at the corner.
1. Which signal takes priority, and what should you do as you approach the junction?
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Obey the officer first. A police officer directing traffic overrides both the flashing amber signal and any road markings. The flashing amber means 'proceed only if the way is clear', but it does not give you priority over the officer's hand signal. Stop before the stop line, not inside the yellow box, because stopping in the box would block the junction if the exit is blocked by the bus. Keep the wheel straight while waiting in case you are shunted. Watch the officer's hand and the pedestrian; the hooded pedestrian may step out. Do not move until the officer clearly releases you and your exit is clear.
2. The diversion sign is partly covered by a branch. How should you decide which route to take?
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The half-covered diversion sign is not reliable enough to commit to a route. Slow to a crawl, use the officer's directions, the visible road geometry and any temporary markings, and look for the continuation of the diversion. If you cannot see a safe path, stop before the junction in a position that does not block it and observe other traffic or ask the officer. Do not guess by following a vehicle that may be turning elsewhere, and never reverse into a live junction. If the left turn is blocked by the bus, wait rather than squeezing past pedestrians. Treat the worn left-turn marking as supporting information only, not as a command.
3. Why does the yellow box junction still matter when the traffic lights are out?
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The yellow box junction still applies when the lights are out because it is a road marking, not a signal. You may enter only if your exit is clear; otherwise you would stop inside the box and block cross traffic, including the bus and emergency vehicles. With the bus partly blocking the left exit, there is a real risk that you would enter and then have nowhere to go. The correct action is to wait before the box until the bus moves or the officer directs you through. This also keeps the junction clear for traffic on the M1, which may be moving unpredictably because of the power failure.