Our Sadie (rip) a poodle/maltese mix was the Sweetest girl ever. Never bothered anything, never met a stranger, honestly was an almost perfect dog..............unless you left her alone after dark! Then she would ALWAYS get into the trash can and string trash all over the house. If we knew we were going to be gone after dark we would take the trash out before we left, and shut the bedroom door. If we forgot to shut all the bedroom doors, she would pee in the middle of whatever bed she could get to. Happened EVERY time we either forgot to take out the trash, or neglected to shut a door and she was left alone after dark.
Maybe it was because she was stressed out by being left alone after dark, or maybe it was because she was mad about being left alone after dark. Seeing as how she always gave us that look like............"told ya I don't like being alone in the dark", I was always inclined to think she did it out of spite. Still loved her sweet fuzzy butt though!