what can cause interior lights to come on when door is closed on 1990 Buick Riviera

interior lightas come on and cause battery to go dead sometimes when at work and car turned off and keys out of ignition i have taken fuse out and also tried disconnect battery (but that is ahassle) would like to fix problem sometimes its back lights sometimes just a couple lights it varies

Asked by for the 1990 Buick Riviera
Check door switches and the connections to the switch.