94 LeSabre Wierd Light Problem

Cannot turn off the parking lights. I need to disconnect the battery to stop it from draining. Could it be the light switch? Any other suggestions?
They were off this morning, and I did not think I turned them on while I was driving this morning.

If you have an aftermarket alarm this can be an issue as some are wired to the parking lights, if not remove the headlite switch and check it out.