Interior lights

I tried searching for this, but the search was a little on the slow side. I have a 97 Cutlass Supreme. Tonight, after a few highway miles and a lot of windshield death, I stopped to clean the bugs off. I cleaned all the windows and when I got back in, the interior lights wouldn't shut off. I wasn't far from home, so I just drove with them on. Once I got home, we opened a door, and the lights went off, closed it, the lights came back on. I checked all the door switches, and they don't effect it either way, it has something to do with the latch on the door. The lights don't come on untill all four doors have the latch engages. Please, somebody have the answer to this problem, I am at a loss.