Re: The Joker's background?
One of the best things about the Joker in this movie is his past was an enigma. One of his scars stories could be true, or they both could be a pack of lies. We'll never know. That just adds to the creepy factor of him. The unknown can be very scary.
"Sometimes I remember it one way. Sometimes another. If I'm going to have a past, I prefer it to be multiple choice!"
- The Joker