Originally Posted by JDonaldD
I recently re-watched TDK again and there are more allusions to what happens to Batman in TDKR than I thought, specifically Joker's claim that Batman will be cast out when he's not needed anymore. You could argue that Bruce comes to believe this along with Harvey's "live long enough to see yourself become the villain" line and takes the opportunity to cast himself out on his own means.
I would argue that Joker wins by the end of TDK. Joker remarks that Batman is truly incorruptible in their last meeting but I would argue because of what happened to Dent, Joker had a hand in forcing Batman to corrupt the Batman symbol. Although their intentions are good, Batman and Gordon become corrupt, which is tragic because corruption is what they were trying to fight.
It's a really compelling ending but in all seriousness, I think it would be easy to spin Dent's story to the public as a victim of the Joker, which is how we see it as audience members.
We as audience members see Dent as a character and, hopefully, a human being. To Gotham, he is a symbol and, more importantly, a politician. How do people usually react when they discover their political leaders are hypocrites? And that's when it's a sex scandal. If it came out that the "Hope and Change" of Gotham became a crazed killer, his legacy would be ruined and all the good he and Batman brought to the city would be undone as the press would crucify the man and the mob's lawyers would have everything he ever did thrown out of court.
It is believable that they'd want to cover up his failings. However, one could argue pinning the crimes on the Joker would be easy.