On 2002 jeep laredo brake lights dont turn on if lights arent on

That does not make any sense. Do the tail lights work? There are supposed to be separate filaments for brake lights, tail lights, and turn signals. In particular the center brake light should not be possible to be confused with tail lights or signals. Does it come on? If not, then you probably have no brake lights at all, and that is probably because of the bad fuse or the switch on the brake pedal for the brake lights.
If there is some sort of cross over between tail light and brake lights, that is usually from a bad light socket ground; which results in current backing up from one system to another. But then each is usually only half brightness.