How can I fix back brake lights ?

I bought a used 2001 Dodge Caravan 7 months ago and today I was doing my normal errands when i noticed that my back brake lights were on even when the van was turned off. I tried to replace the fuse but that didn't fix the problem. Please help. What is this ? How do I fix this ? Please help

The brake light don't require the ignition to be on to light up. Your problem means that the switch on the end of the brake pedal is stuck on.