The Warning of Sideshow Bob!

From The Simpsons episode The Black Widower where Sideshow Bob marries Bart's aunt Selma with the intention of murdering her on their wedding night by blowing her up in a hotel room full of natural gas (oops sorry for the spoiler):

Sideshow Bob, "But wait, if you saved Selma, why did the room explode?"

Chief Wiggum: "Me and the boys were celebrating a job well done," [cut to Wiggum, Homer, and a few cops smoking cigars] "When I threw my match in the vicinity of the crime scene."

The police start to take Sideshow Bob away, and he yells, "I'll be back. You can't keep the Democrats out of the White House forever. And when they get in, I'm back on the streets, with all my criminal buddies!" (Maniacal laughter).