Aspects of the disclosure involve a collision mitigated braking system employed in vehicles operating in a self-driving (autonomous) mode. Collision mitigated braking provides redundancy to the vehicle's main driving system in emergency situations. The collision mitigated braking system is configured to cause the vehicle to come to a stop when an imminent collision is perceived and the main driving system has not initiated a braking maneuver. A perception component employs information received from vehicle sensors, analyzing the sensor data to identify nearby objects of interest that are determined to be in the vehicle's path or that could otherwise collide with the vehicle. A control component evaluates the objects of interest to determine whether immediate braking is required. If this is the case and the main driving system has not begun to brake, the control component causes the vehicle to perform immediate braking to avoid a possible collision.