Abstract: A safety or emergency brake system for a slow moving off-road passenger vehicle has a brake lever that is adapted to pivot into contact with a wheel-mounted flexible tire that partially supports the vehicle and then be further pivoted by the tire, as it rotates in a forward direction due to vehicle inertia, into an interference position with the tire that locally deflects the tire to prevent further wheel rotation. The brake is activated by a device sensing impending vehicle impact with an obstacle, or by the vehicle operator, and is initially released by rotation of the tire in a reverse direction as the vehicle is caused to reverse or move backward.