An automated driving system and methods are disclosed. The automated driving system includes a perception system disposed on an autonomous vehicle. The automated driving system can detect, based on images captured using the perception system, a traffic officer wielding a traffic signal device such as the traffic officer's hand, or a wand, sign, or flag. The automated driving system can also determine whether the traffic officer is directing a traffic signal to the autonomous vehicle with the traffic signal device, and if so, determine whether content of the traffic signal is recognized. If the content of the traffic signal is recognized, the autonomous vehicle can respond in a manner consistent with the content of the traffic signal. If the content of the traffic signal is not recognized, the autonomous vehicle can respond by treating the traffic signal as a stop signal.