If the brake lights do not shut off the electrical switch at the brake pedal must have failed. With the driver's door open, kneel at the driver's door opening, look at the brake pedal assembly, you will see an electrical switch with 2 wires (perhaps 4 if you have cruise control). Disconnect the electrical connector ans see if the rear lights go out. A new brake light switch must be fitted with a certain clearance between the tip of the switch and the brake pedal. Incorrect fitment of the switch may cause the brakes to drag.