The invention relates to a driver assistance system for a motor vehicle, comprising a speed detection device (22) for detecting driving data in the form of a speed (vk) of the motor vehicle (10), a preceding vehicle detection device (14), which comprises as a first component at least one video camera (18) and as a second component at least one distance sensor (20), for detecting driving data in the form of a distance (A) from a preceding vehicle (16) driving in front of the motor vehicle (10), a preceding vehicle speed determination device for determining driving data in the form of a preceding vehicle speed (vVf) of the preceding vehicle (16), and an electric control unit (28), which is equipped to trigger an autonomous deceleration of the motor vehicle (10) with the presence of predetermined brake trigger driving data and to terminate the autonomous deceleration of the motor vehicle (10) with the presence of predetermined brake abortion driving data. According to the invention, the electric control unit (28) is equipped to carry out a method comprising the following steps: redundant detection of preceding vehicle driving data (A, vVf) of the preceding vehicle (15), and non-redundant detection of the preceding vehicle driving data (A, vVf) if a redundant detection of the preceding vehicle driving data (A, vVf) is not possible, comparing the non-redundantly detected preceding vehicle driving data to preceding vehicle driving data redundantly detected within a predetermined time (t), and using the non-redundantly detected preceding vehicle driving data in order to carry out step (d) if the non-redundantly detected preceding vehicle driving data correspond to the redundantly detected preceding vehicle driving data.