What action can defensive drivers take to alert those behind them when they plan to stop?

Defensive drivers can alert those behind them by tapping their brakes. This action serves to gently illuminate the brake lights without coming to a complete stop, providing a clear signal to drivers following behind that the vehicle is slowing down. Tapping the brakes creates awareness without causing alarm, allowing drivers to prepare to stop safely.

This approach is preferable as it helps maintain a steady flow of traffic while giving adequate notification to other drivers. In contrast, slamming the brakes abruptly can cause panic or lead to collisions, as it does not provide a gradual warning. Using hazard lights is generally reserved for situations where a vehicle is stopped or moving unusually slowly, rather than for routine stopping. Signaling with a horn might confuse other drivers in the context of stopping, as horns are typically used to indicate warning or alert for immediate hazards rather than a simple stop. Thus, tapping the brakes is the most effective and safest way to communicate an intention to stop to others on the road.