If the passenger seat of your car had a foot brake so the passenger could decide when to brake while you were driving, would that make your driving safer?<p>Cars already ignore driver braking input when it would be dangerous - that&#x27;s what ABS is, after all, selective releasing of the brakes on locked wheels.<p>I can think of plenty of circumstances where a passenger just slamming on the brakes could put a self driving car in more danger.<p>Still, no reason not to have a &#x27;pull cord in case of emergency&#x27; type brake for passengers to use to signal the car to stop as soon as can be safely managed.