A driver who reverses into a vehicle behind them while under violent attack may not be in breach of duty of care where the response accords with that of a reasonably prudent person acting in the agony of the moment, even where the driver had earlier failed to observe the vehicle behind. The reasonableness of the emergency response is assessed prospectively from the moment of the emergency, not with the benefit of hindsight. However, the question of whether a pre-existing failure of observation precludes reliance on the agony of the moment principle was the subject of disagreement ([name withheld] dissenting).
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