An advanced driver assistance system of a vehicle for performing one or more driver assistance features includes an environmental sensor, a driving status monitor, an activation switch, and a driver assistance controller. The environmental sensor detects an environment surrounding the vehicle. The driver status monitor monitors the driver and determines an abnormal situation of the driver. The activation switch is operable by the driver for activating or deactivating the driver assistance features. The driver assistance controller performs the one or more driver assistance features for controlling the vehicle based on a target behavior, where the target behavior is defined based on the environment surrounding the vehicle. The driver assistance controller activates the driver assistance features when the driver status monitor detects the abnormal situation with the activation switch set to deactivate.
