lights wont shut off .. help

[str33tpr3p]

hey guys im having a issue with the lighting on my car.. i just rebuild my downpipe so car was off the road for 3 weeks. i go to start it up it was dead which i expected so i charged it everything was fine went to start up later that night it was dead again. thats what i realized that my running tail lights arent shutting off, even when the car is off they are still running. i have to disconnect the battery every time so my car doesnt die. any clue what it might be? i honestly dont even know where to start.

PLEASE HELP