A system for disabling the operation of a vehicle when a driver of a vehicle is seated in a vehicle seat. The system includes an alcohol detection sensor configured to be contacted by the driver and to generate a detection signal based on contact between the driver and the detection sensor. The system also includes a sensing electrode located proximate to the occupant and a sensing circuit configured to provide a sensing signal to the sensing electrode. A controller is provided to detect a change in the detection signal resulting from contact between the driver and the detection sensor. The controller is configured to disable the vehicle when either the blood alcohol concentration of the driver of the vehicle exceeds a threshold or the controller does not detect a change in the detection signal resulting from contact of the driver with the detection sensor.