Okay so Im bored at work and I was thinking about ways in which Begins might work as a prequel to Burton's Batman, and I think that it actually could be possible with some clever logic.
But Joe Chill killed his parents in Begins, not Jack Napier!
Yes that's true. But I'd like to refer to something that Valman said in Batman Forever when he was trying to disuade Robin from seeking revenge on Two-Face. He told him that once one gets revenge, their desire doesn't end there and they continue to seek out a "new face." Perhaps in "Batman," Bruce had flashbacks of Jack Napier killing his parents because Chill's murder gave him that thirst for revenge. When Batman says to Joker that he "made him," he didn't mean it literally. If you listen to Joker's response it isn't even that serious, so it works if you look at it that way.
But the Joker already exists at the end of Begins, which contradicts Batman!
Not necesarilly. All we know from the ending of Begins is that there is a criminal out there with the flair for the dramatic as shown by the playing card. Well Napier was already a criminal and he doesn't have to be the Joker to leave a card. Lots of criminals do that. IIRC he always used to play with that deck of cards that he had. The reference in Begins could just be to some regular crime that Napier had committed.
Interesting, tell me more!
Well the DA died in Begins, explaining why there's a new DA in Batman. The manor burned down in Begins, explaining why it doesn't look the same in Batman. I don't think we ever saw Wayne Enterprises in Batman so it's not a logical error that there's no mention of Lucious. Um, yea, so it could work!